CHE 105

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The shielding effect refers to the 1 [reduction, increase] of the effective nuclear charge of the nucleus by the presence of 2 [core, valence] electrons. 1. 2.

1. reduction 2. core

13. What is the name of the compound Ba(OH)2? a. barium oxyhydride b. barium hydrogen oxide c. barium hydroxide d. barium hydrate

13. c

22. Which aqueous solution will have the highest concentration of chloride ions? a. 0.10 M NaCl b. 0.15 M MgCl2 c. 0.12 M AlCl3 d. 0.25 M KCl

22. c

Select the true equality. A. 1 ms = 1000 μs B. 1 ns = 109 s C. 1 s = 103 ks D. 10-12 ps = 1 s

Select the element with the greatest metallic character. A. Na B. Rb C. Mg D. Sr

The average home lawn is 10871 square feet (ft2). What is the size in square meters (m2)? A. 3212.5 m2 B. 1009.9 m2 C. 8283.7 m2 D. 12,871 m2

What is the atomic mass of tin? A. 47.87 u B. 50 u C. 118.71 u D. 22 u

Use the bond energies provided to estimate ΔH°rxn for the reaction below. XeF2 + 2 F2 → XeF6 ΔH°rxn = 1 kJ Bond Bond Energy (kJ/mol) Xe—F 147 F—F 159 Report your answer as a whole number. Do NOT use scientific notation in your answer. 1.

-270|-270.|-271|-269|

When 10. grams of Mg react in the presence of excess N2 , how many moles of Mg3N2 areproduced? 3 Mg(s) + N2(g) → Mg3N2(s) 1 mol Mg3N2 Report your answer with two significant figures. Do NOT include units in your answer. 1.

0.14

Calculate the specific heat of a metal if 46.5 g of the metal at 78.0 °C warms 32.0 g of water at 23.1 °C to 36.1 °C. The specific heat of water is 4.18 J/g°C. Specific heat of metal = 1 J/g°C Report your answer with three significant figures. Do NOT include units in your answer. For numbers in scientific notation, use the format 2.22E2 or 2.22E-2. 1.

0.892

The oxidation number of phosphorus in CaHPO3 is 1 [+ or -] 2 [a whole number]. 1. 2.

1. + 2. 3|three|

Determine the oxidation number for each element in KMnO4. K 1 Mn 2 O 3 You must include a number and a sign (+ or -) for each answer. 1. 2. 3.

1. +1|1+| 2. +7|7+| 3. -2|2-|

Use the data provided to calculate ∆Hrxn for the following reaction: 4NH3(g) + 5O2(g) →4NO(g) + 6H2O(g) N2(g) + O2 (g) →2NO (g) ∆H = -180.5 kJ N2(g) + 3H2(g) →2NH3 (g) ∆H = -91.8 kJ 2H2(g) + O2(g) →2H2O (g) ∆H = -483.6 kJ Report your answer to one decimal point. Do NOT include units in your answer. Do NOT use scientific notation. ΔHrxn = 1 kJ 1.

1. -1628.0|-1628.1|-1628.2|-1628.3|-1628.4|

The number of unpaired electrons in a neutral atom of krypton in its ground state is 1 . Report your answer as a whole number. The electron configuration of this atom indicates that it is 2 [diamagnetic, paramagnetic]. 1. 2.

1. 0|zero| 2. diamagnetic

What is the wavelength (in nm) of a proton accelerated to near the speed of light at 2.90 ×108 m/s. The mass of a proton is 1.673 ×10-27 kg. 1 nm Report your answer with three significant figures. Do NOT include units in your answer. Use the format 2.22E2 or 2.22E-2 for numbers in scientific notation. 1.

1. 1.37E-6|1.36E-6|

A ground-state Cl atom has 1 core electrons and 2 valence electrons. Report each answer as a whole number. Do NOT include units in your answer. 1. 2.

1. 10 2. 7

Complete the table for each ion. Use whole numbers for numeric answers. Do NOT include units in your answers. Ion Number of protons Number of electrons Choose one: cation or anion Al3+ 1 2 3 Se2- 4 5 6 1. 2. 3. 4. 5. 6.

1. 13 2. 10 3. cation 4. 34 5. 36 6. anion

A neutral atom of chlorine-35, contains 1 protons, 2 neutrons, and 3 electrons. 1. 2. 3.

1. 17 2. 18 3. 17

How many electrons in an atom can have these sets of quantum numbers? Enter you answer a whole number. n = 3 1 n = 3, l = 2 2 n = 3, l = 2, ml= 2 3 n = 3, l = 2, ml = 2, ms = -½ 4 1. 2. 3. 4.

1. 18 2. 10 3. 2 4. 1

What is the ground state electron configuration for nitrogen? 1 Use the format 1s2 2s2 (without superscripts, or carets ^, and with spaces as indicated). How many valence electrons are in a ground state nitrogen atom? 2 1. 2.

1. 1s2 2s2 2p3|[He] 2s2 2p3| 2. 5

For each blank, give the number of electrons in an atom that can have the given set of quantum numbers: n = 4, l = 1, ml = -1, ms = +½: 1 n = 2, l = o, ml= 0, ms = -½: 2 1. 2.

1. 1|one| 2. 1|one|

Balance the following chemical equation with the smallest possible whole numbers by filling in each blank with the proper coefficient. If the coefficient is 1, fill in 1. 1 Fe(NO3)3 + 2 MgO → 3 Fe2O3 + 4 Mg(NO3)2 1. 2. 3. 4.

1. 2 2. 3 3. 1 4. 3

Provide the charge of each. (For the elements, provide the most stable ion charge). S 1 Al 2 SO3 3 H2PO4 4 1. 2. 3. 4.

1. 2-|-2| 2. 3+|+3| 3. 2-|-2| 4. 3-|-3|

Given the reaction R + X →Q + Z ΔH = 11 kJ There are 1 kJ of heat 2 (absorbed, given off) when 2 moles of R reacts with 3 moles of X. For blank 1, report your answer with two significant figures. Do NOT include units in your answer. Do NOT use scientific notation. 1. 2.

1. 22 2. absorbed

The molar volume of a gas at STP is 22.4 L/mol. This means that at a temperature of 1 K and a pressure of 2 atm that 3 L will contain 4 moles. Fill in each blank with the appropriate numerical values, each to three significant figures. 1. 2. 3. 4.

1. 273 2. 1.00 3. 1.00 4. 22.4

What is the atomic number of lithium? 1 The number of protons in an atom of lithium is 2 . This is true for 3 [all, most, some, a few] atoms and ions of lithium. 1. 2. 3.

1. 3 2. 3 3. all

How many protons and electrons are in an atom of selenium that has a -2 charge? Report each answer as a whole number. Do NOT include units in your answer. Number of protons = 1 Number of electrons = 2 1. 2.

1. 34 2. 36

Fill in the chart for each ion. Ion number of protons number of electrons Choose one: cation or anion Se2- 1 2 3 Cu+ 4 5 6 1. 2. 3. 4. 5. 6.

1. 34 2. 36 3. anion 4. 29 5. 28 6. cation

Balance the following chemical equation with the smallest possible whole numbers by filling in each blank with the proper coefficient. If the coefficient is 1, fill in 1. 1 NH3 + 2 O2 → 3 NO+ 4 H2O 1. 2. 3. 4.

1. 4 2. 5 3. 4 4. 6

What are the coefficients of the balanced equation when balanced with the smallest possible whole numbers? 1 NH3 + 2 O2 → 3 NO + 4 H2O Enter your responses as whole numbers. 1. 2. 3. 4.

1. 4 2. 5 3. 4 4. 6

Strontium salts are used in red fireworks, emitting light with a wavelength of 635 nm. What is the frequency of the emitted light? Report your answer with three significant figures. Use the format 2.22E2 or 2.22E-2 for scientific notation. Do NOT include units in your answer. 1 Hz 1.

1. 4.72E14|4.72e14|

Calculate the mass of sodium hydroxide, in grams, in 500. mL of a 0.25 M NaOH solution. 1 g NaOH Report your answer with two significant figures. Do NOT include units in your answer. 1.

1. 5.0|4.9|

Fill in the blanks to construct the isotopic symbol for the isotope with 30 protons and 40 neutrons. 1 2 1. 2.

1. 70 2. Zn

Convert 0.929 atm to mmHg. 1 mmHg Report your answer with three significant figures. Do NOT include units in your answer. 1.

1. 706

Match the compound on the right with the hybridization of its central atom on the left by putting the letter in the blank. Hybridization of central atom Compound 1 sp A CO2 2 sp2 B H2O 3 sp3 C SO2 1. 2. 3.

1. A 2. C 3. B

In Rutherford's Gold Foil Experiment, alpha particles were targeted to a sheet of gold foil. 1 [All, Most, A few] of the alpha particles bounced off the gold foil. This lead to the understanding that "Plum Pudding Model" of the atom was 2 [valid, invalid] and lead to the understanding that most of the 3 [mass, electrons] of the atom were concentrated in the center of the atom. We call this center of the atom the 4 . 1. 2. 3. 4.

1. A few|few| 2. invalid 3. mass 4. nucleus

Use the letters below to select the electron group geometry and the molecular geometry for the XeF4 molecule. A. Tetrahedral B. Square planar C. Trigonal bipyramidal D. Seesaw E. Square pyramid F. Octahedral Electron group geometry 1 Molecular geometry 2 1. 2.

1. F 2. B

Arrange the following atoms in order of increasing atomic radii (from smallest to largest): F I Li C 1 < 2 < 3 < 4 1. 2. 3. 4.

1. F 2. C 3. Li 4. I

Fill in the missing element symbol or name. Element Symbol Element Name 1 potassium 2 silver Hg 3 Ar 4 1. 2. 3. 4.

1. K 2. Ag 3. mercury 4. argon

In the reaction below, what element is being oxidized? What element is the reducing agent? Mg(s) + 2 HCl(aq) →MgCl2(aq) + H2(g) 1 is being oxidized. 2 is the reducing agent. 1. 2.

1. Mg 2. Mg

Provide either the missing symbol or the missing element name for each. Element Name Element Symbol 1 B iron 2 potassium 3 1. 2. 3.

1. boron 2. Fe 3. K

1. Which one is an extensive property? a. color b. taste c. density d. surface area

1. d

According to Pauli's exclusion principle, if two electrons have the same spin quantum number, they must belong to 1 [same, different] orbitals. 1.

1. different|Different|

For each symbol or formula, fill in the blank with one of the words in the header of the table. Element or compound? Atomic or molecular? Ar 1 2 P4 3 4 1. 2. 3. 4.

1. element 2. atomic 3. element 4. molecular

Label each process as endothermic or exothermic. Baking a cake in the oven. 1 Boiling water on the stove. 2 Burning a match. 3 1. 2. 3.

1. endothermic 2. endothermic 3. exothermic

X-rays are 1 [higher, lower] in energy than visible light. Radio waves are 2 [higher, lower] in energy than visible light. 1. 2.

1. higher 2. lower

Provide either the missing symbol or the missing element name for each. Element Name Element Symbol 1 Pb carbon 2 tungsten 3 1. 2. 3.

1. lead 2. C 3. W

Because the effective nuclear charge of nitrogen is 1 [greater than, equal to, less than] fluorine, the atomic radius of nitrogen is 2 [greater than, equal to, less than] fluorine. 1. 2.

1. less than 2. greater than

Because the effective nuclear charge of carbon is 1 [greater than, equal to, less than] nitrogen, the atomic radius of carbon is 2 [greater than, equal to, less than] nitrogen. 1. 2.

1. less than|less| 2. greater than|greater|

A solution of Ba(OH)2 is added to a solution of HNO3. The reaction is a 1 [precipitation, neutralization, oxidation-reduction] reaction. The salt formed as a product of this reaction is 2 . Enter the formula without subscripts or spaces and using parentheses if needed, e.g., C4H4O2 or (NH4)2S. 1. 2.

1. neutralization|neutralization reaction| 2. Ba(NO3)2

The cell phone is determined to have a mass of 1.3062 ×102 g. Is that the SI unit for mass? 1 [choose: yes or no]. Rewrite that mass using standard notation and include all digits in your answer. 2 Do NOT include units in your answer. 1. 2.

1. no 2. 130.62

SF6 is a 1 [polar, nonpolar] molecule containing 2 [polar, nonpolar] bonds. 1. 2.

1. nonpolar 2. polar

Fill in each blank with the word physical or chemical. The temperature that ice melts is a 1 property. The fact that an iron nail will rust is a 2 property. When coal (mainly carbon) will burn in the presence of oxygen to produce carbon dioxide. This is an example of a 3 property. 1. 2. 3.

1. physical 2. chemical 3. chemica

Fill in each blank with the word physical or chemical. The melting point of water is a 1 property. The rate of corrosion of steel is a 2 property. The color of a copper chloride solution is a 3 property. 1. 2. 3.

1. physical 2. chemical 3. physical

The atomic number determines the number of 1 [electrons, neutrons, protons] in an atom or ion. The atomic number of sodium is 2 . 1. 2.

1. protons 2. 11|eleven|Eleven|

Choose from the following words to complete the sentence: solute, solvent, solution, molarity, dilution. A 1 is a homogeneous mixture made of a 2 (substance in the lesser quantity) and a 3 (substance in the greater quantity). 1. 2. 3.

1. solution 2. solute 3. solvent

Give the name of the molecular geometry of XeF4. 1 1.

1. square plane|square planar|

A 1 [strong acid, weak acid, strong base, weak base] is a substance that ionizes 100% in water to produce H3O+ (or H+) ions. HNO3 is an example of a 2 [strong acid, weak acid, strong base, weak base]. . 1. 2.

1. strong acid 2. strong acid

Provide the name of each polyatomic ion. SO3 2— 1 NO2— 2 Provide the charge of each polyatomic ion. Report your answers as a number and a sign (+ or -). Do NOT include the name or formula of the ion. phosphate: PO4?? ?? = 3 ammonia: NH4?? ?? = 4 1. 2. 3. 4.

1. sulfite 2. nitrite 3. 3-|-3| 4. +|+1|

Classify each element as a main group metal, transition metal, nonmetal, or metalloid. Element Classification V 1 Sr 2 Se 3 1. 2. 3.

1. transition metal 2. main group metal 3. nonmetal

Rank x-rays, microwaves, and visible light in order of increasing (shortest to longest) wavelength. shortest 1 < 2 < 3 longest 1. 2. 3.

A sample of gas has an initial volume of 5.6 L at a pressure of 2.0 atm. If the volume of gas is increased to 9.4 L, what is the pressure, in atm? 1 atm Report your answer with two significant figures. Do NOT include units in your answer. 1.

1.2

If 32.50 mL of 5.05 M NaH2PO4 solution is diluted to 100.0 mL, what is the final concentration of NaH2PO4? Report your answer with three significant figures. Do NOT include units in your answer. 1 M 1.

1.64

10. Which group includes only transition elements? a. Te, Co, Ni b. Ca, Zr, Sb c. Sc, Fe, Os d. Cl, V, Ni

10. c

11. Which one is a molecular compound? a. FeS b. SCl2 c. SrCl2 d. TiF4

11. b

12. What is the chemical formula for potassium hydrogen carbonate? a. KHCO3 b. K2CO3 c. K(HCO2) d. K(HCO3)2

12. a

What is the result of the calculation? Report your answer with the correct number of significant figures. 3.14159 + 9.2 = 1 1.

12.3

14. What is the name of the acid produced when hydrogen bromide (HBr) gas dissolves in water? a. hydroxybromic acid b. bromic acid c. hydrobromic acid d. hydrogen bromide acid

14. c

15. Which one does not represent one mole of the indicated element? a. 6.022 × 1023 C atoms b. 20.18 g of Ne c. 65.38 g of Zn d. 26.0 g of Fe

15. d

A burst of green light (wavelength 550 nm) has a total energy of 5.50 ×10-17 J. How many photons does it contain? Report your answer with three significant figures. Do NOT include units in your answer. Use the format 2.22e2 or 2.22e-2 for scientific notation. 1 photons 1.

152|1.52e2|

16. Which sample contains the greatest number of atoms? a. 120 g of Pb b. 2.0 mol of Ar c. 5.0 g of He d. 2.0 × 106 O2 molecules

16. b

17. How many moles of anions are in 25.0 g of PbO2 (formula mass = 239.2 g/mol)? a. 0.676 mol b. 0.209 mol c. 0.887 mol d. 0.436 mol

17. b

18. Which is not an SI base unit? a. m b. min c. kg d. K

18. b

What is the mass in grams of 1.33 mol of salicylic acid, C7H6O3? 1 g Report your answer with three significant figures. Do NOT include units with your answer. 1.

184

19. Which one contains 23.8% carbon by mass? a. CH3Cl (50.49 g/mol) b. CH3F (34.033 g/mol) c. CH5N (31.058 g/mol) d. CH3Br (94.939 g/mol)

19. a

How many zeros are significant in 0.001030 g? Report your answer as a whole number. Do NOT include units in your answer. 1 1.

2. Which group includes an element, a compound, and a mixture (listed in any order)? a. nitrogen, sucrose, water b. water, carbon dioxide, platinum c. mercury(II) oxide, ice cream, air d. water, salad dressing, copper

2. d

27.8 L = 1 cm3. Report your answer with three significant figures. Do NOT include units in your answer. Report answers in scientific notation with the format 2.22E2 or 2.22E-2. 1.

2.78E4|27800

Calculate the mass (in kilograms) of 4.5 ×1025 atoms of potassium. 1 kg Report your answer with two significant figures. Do NOT include units in your answer. 1.

2.9

Write 0.000297 in scientific notation. 1 Report your answer with three significant figures. Use the format 2.22E2 or 2.22E-2 for scientific notation. 1.

2.97e-4

20. What is the empirical formula of a compound that is 62.0% C, 10.4% H, and 27.5% O by mass? Fill in the blanks to complete the formula. Enter a "1" if the value is 1. The numbers will not be subscripted. C______H______O______

20. 3 6 1

21. The empirical formula for a compound is C6HO3, and its molar mass is 242 g/mol. What is the molecular formula of the compound? Fill in the blanks to complete the formula. Enter a "1" if the value is 1. The numbers will not be subscripted. C______H______O______

21. 12 2 6

The top speed of a Formula 1 race car is 340. kilometers per hour. What is the speed in miles per hour? Report your answer with three significant figures. Do NOT include units in your answer. 1 mi/h 1.

211

23. X3H8 burns in oxygen to produce XO2 and water. What is the stoichiometric coefficient for oxygen when the chemical equation for this reaction is balanced using the lowest, whole-number coefficients?

23. 5

What is the molarity of a solution in which 190. g of NH4NO3 are dissolved in enough water to make 100. mL of solution? The molar mass of NH4NO3 is 80.04 g/mol. 1 M NH4NO3 Report your answer with three significant figures. Do NOT include units in your answer. 1.

23.7

24. When aqueous solutions of KBr and AgC2H3O2 are mixed, what is the ionic equation for the resulting solution? a. K+(aq) + Br‒(aq) + Ag+(aq) + C2H3O2‒(aq) → K+(aq) + C2H3O2‒(aq) + AgBr(s) b. K+(aq) + Br‒(aq) + Ag+(aq) + C2H3O2‒(aq) → KC2H3O2(aq) + AgBr(aq) c. K+(aq) + Br‒(aq) + Ag+(aq) + C2H3O2‒(aq) → KC2H3O2(s) + AgBr(s) d. K+(aq) + Br‒(aq) + Ag+(aq) + C2H3O2‒(aq) → KC2H3O2(s) + Br‒(aq) + Ag+(aq)

24. a

25. What are the oxidation numbers of each of the elements in the hypothetical XO4‒ anion? Fill in the blanks with a number and a sign for your answers. X: ______ O: ______

25. +7 - 2

26. How many grams of oxygen are formed when 6.21 moles of KOH are produced according to the reaction below? The molar mass of O2 is 31.998 g/mol. 4 KO(s) + 2 H2O(l) → 4 KOH(s) + O2(g)

26. 49.7 g

27. What is the percent yield of a reaction that produces 28.6 g of Fe when 50.0 g of Fe2O3 (159.687 g/mol) react with excess Al according to the following reaction? Fe2O3(s) + 2 Al(s) → Al2O3(s) + 2 Fe(s

27. 81.8 %

28. In an acid-base titration, 38.74 mL of 0.500 M potassium hydroxide react with 50.00 mL of sulfuric acid solution to reach the equivalence point. What is the concentration of the H2SO4 solution? Hint: Start by writing a balanced reaction equation. a. 0.194 M H2SO4 b. 0.387 M H2SO4 c. 0.0969 M H2SO4 d. 0.257 M H2SO4

28. a

29. Which substance (with specific heats provided) would show the greatest temperature change upon absorbing 100.0 J of heat? a. 10.0 g Ag, cAg = 0.235 J/g·oC b. 2.0 g H2O, cH2O = 4.184 J/g·oC c. 10.0 g Fe, cFe = 0.442 J/g·oC d. 20.0 g Au, cAu = 0.129 J/g·oC

29. a

3. What is the volume of a 2.5 g block of metal if its density is 4.75 g/cm3? a. 1.0 cm3 b. 0.53 cm3 c. 2.5 cm3 d. 4.8 cm3

3. b

A 0.500 mol sample of I2 contains 1 I2 molecules. Report your answer with three significant figures. Do NOT include units in your answer. Report answers in scientific notation with the format 2.22E2 or 2.22E-2. 1.

3.01E23

A student discovers a gold nugget that weighs 909 kg and decides to share it evenly with his chemistry student peers. If there are 2.41×103 chemistry students, how many kg of gold does each student receive? 1 kg Report your answer with three significant figures using the format 2.2e2 or 2.2e-2 for scientific notation. Do NOT include units in your answer. 1.

3.77e-1|3.77E-1|0.377|.377|

30. From the ΔHof values provided, what is ΔHorxn for the reaction below? C2H4(g) + 3 O2(g) → 2 CO2(g) + 2 H2O(l) ΔHorxn = ? ΔHof (kJ/mol) C2H4(g) +52 H2O(l) -286 CO2(g) -394 a. -1256 kJ b. +1609 kJ c. -1412 kJ d. -822 kJ

30. c

31. How many photons are contained in a flash of yellow light (589 nm) from a lamp that emits 609 kJ of energy? a. 4.03 × 1028 photons b. 3.37 × 1019 photons c. 2.48 × 1025 photons d. 1.80 × 1024 photons

31. d

32. What is the wavelength of light associated with the transition from n = 1 to n = 3 in the hydrogen atom? a. 103 nm b. 85.1 nm c. 134 nm d. 211 nm

32. a

33. What is the de Broglie wavelength (in m) of an electron (mass = 9.109 × 10‒31 kg) with a velocity of 6.00 × 106 m/s? Report your answer with two significant figures. Enter your answer in scientific notation with the format 2.2E2 or 2.2E-2. Do NOT include units in your answer.

33. 1.2 × 10‒10 m

34. Which one of the following is diamagnetic? a. Si b. Cs c. Zr2+ d. Hg2+

34. d

35. What is the ground-state electron configuration for the 6th element in period 5 of the periodic table? a. [Kr]5s14d5 b. [Kr]5s24d4 c. [Ar]5s24d5 d. [Kr]5s25d5

35. a

36. Of the following, which atom has the smallest atomic radius? a. K b. As c. Rb d. Sb

36. b

What is the mass of 1.35 moles of aluminum? Report your answer with three significant figures. Do NOT include units in your answer. 1 g 1.

36.4

37. Assuming each can form, which of these atoms and ions is smallest? a. C b. C- c. C+ d. C, C- and C+ are the same size.

37. c

38. Which of the following elements has the highest third ionization energy? a. Se b. Ga c. Ca d. As

38. c

39. Which one is not isoelectronic with the other atoms or ions shown? a. Ge b. As+ c. Ga‒ d. Se2‒

39. d

4. What is the answer to the calculation below? 4.1 + (2.718)3 × 3.845 = ? a. 81 b. 81.3 c. 8.1 × 102 d. 81.30

4. b

How many molecules are in 7.22 moles of caffeine (C8H10N4O2)? 1 molecules Report your answer with three significant figures. Do NOT include units in your answer. Use the format 2.22E2 or 2.22E-2 for numbers in scientific notation. 1.

4.35e24

What is the energy of the photon emitted when an electron in a hydrogen atom transitions from the n=6 level to the n=2 level? Report your answer with two significant figures. Do NOT include units in your answer. Use the format 2.2E2 or 2.2E-2 for scientific notation. 1 J 1.

4.8E-19|4.7E-19|4.9E-19|4.8e-19|4.7e-19|4.9e-19|

40. Which of these bonds is the most polar? a. C‒O b. N‒O c. N‒S d. O‒Cl

40. a

41. According to Lewis theory, what would be the chemical formula of the compound formed when X, an element in group 13, reacts with Y, an element in group 15 of the periodic table? a. XY b. X2Y3 c. X3Y2 d. X2Y

41. a

42. Which two of the following molecules or ions exhibit resonance structures? Partial credit will not be given. a. CO32‒ b. NCl3 c. NO2‒ d. OCl2

42. a/c

43. What is the formal charge on the central Cl atom of the Cl3‒ anion? a. +2 b. +1 c. 0 d. ‒1

43. d

44. From the bond energies provided, estimate ΔHorxn for the reaction below. PCl3(g) + Cl2(g) → PCl5(g) ΔHorxn = ? Bond Bond energy Cl‒Cl 243 kJ/mol P‒Cl 331 kJ/mol a. ‒419 kJ b. ‒243 kJ c. ‒662 kJ d. ‒905 kJ

44. a

45. Which ionic compound has the highest lattice energy? a. SrO b. In2O3 c. BaCl2 d. Rb2O

45. b

46. Which of the following molecules displays the smallest bond angle? a. NH3 b. BF3 c. CH3F d. XeF4

46. d

What is the result of the calculation below? 107.3 ÷2.2 -1.7 = 1 Report your answer with the correct number of significant figures. Only answers with the correct number of significant figures will receive credit.

47. Which molecule exhibits the largest total number of lone pairs of electrons? a. CO2 b. NF3 c. XeF2 d. NH2F

47. b

What is ΔH for the reaction 2 CH3OH(l) → 2 C(s) + 4 H2(g) + O2(g) given C(s) + 2 H2(g) + ½ O2(g)→ CH3OH(g) ΔH = -238.4 kJ. 1 kJ Report your answer with four significant figures. Do NOT include units with your answer. 1.

476.8|+476.8|4.768e2|

48. The electron geometry of the difluoride compound of a noble gas in the 4th period or beyond is ________ and the molecular geometry is___________. a. trigonal bipyramidal, linear b. tetrahedral, bent c. trigonal planar, bent d. octahedral, linear

48. a

49. Which molecule is nonpolar? a. AsCl5 b. CF2Cl2 c. SCl2 d. GeH2Br2

49. a

5. How many kL are contained in a 1.25 × 108 cL sample? a. 1.25 × 103 kL b. 1.25 × 104 kL c. 1.25 × 1012 kL d. 1.25 × 1013 kL

5. a

50. Which of the following molecules have sp3 hybridization on the central atom? Select all that apply. Partial credit will not be given. a. XeCl4 b. SF4 c. CH4 d. H2O

50. c/d

52. How many of the following molecules contain at least one pi bond? C2H6 C2Cl4 SeS3 a. 0 b. 1 c. 2 d. 3

52. c

54. If ten moles of oxygen gas at 20.0oC are heated to 350oC while the volume is kept constant, the density of the gas a. increases. b. decreases. c. remains the same. d. cannot be determined.

54. c

55. A sample of gas initially has a volume of 659 mL at 565 K and 2.20 atm. What will be the pressure of the gas if the volume is compressed to 169 mL while the temperature is increased to 815 K? a. 2.05 atm b. 12.4 atm c. 8.53 atm d. 9.83 atm

55. b

56. The density of a gas is 2.05 g/L at STP. What is the gas? a. hydrogen chloride b. sulfur trioxide c. nitrogen dioxide d. dihydrogen sulfide

56. c

57. In a gas mixture of nitrogen, oxygen and neon, the mole fraction of N2 is 0.55 and the mole fraction of Ne is 0.25. If the mixture is at STP in a 5.0 L container, how many O2 molecules are present? a. 1.6 × 1022 molecules b. 6.7 × 1022 molecules c. 3.1 × 1023 molecules d. 2.7 × 1022 molecules

57. d

58. What volume of H2S (at 375 K and 1.20 atm) is needed to produce 55.0 g of sulfur by the reaction shown below? Assume that SO2 is present in excess. 2 H2S(g) + SO2(g) → 3 S(s) + 2 H2O(g) a. 6.83 L b. 29.3 L c. 14.2 L d. 45.5 L

58. b

59. A mixture of equal amounts of N2, O2, and NO gases in a container effuse through the same hole. Which gas is slowest to escape from the container? a. NO b. N2 c. O2 d. It is impossible to determine from the information provided.

59. c

6. If an object has a density of 8.65 g/cm3, what is its density in units of kg/m3? a. 8.65 × 10-3 kg/m3 b. 8.65 × 10-7 kg/m3 c. 8.65 × 103 kg/m3 d. 8.65 × 10-1 kg/m3

6. c

Calculate the energy of electromagnetic radiation emitted from a radio station with a frequency of 96.1 MHz. 1 joules Report your answer using three significant figures. Use scientific notation in the format 2.22e3 or 2.22e-3. Do NOT include units in your answer. 1.

6.37e-26

60. Which equation can be used to calculate the properties of a gas under nonideal conditions? a. the holistic gas equation b. the van Deemter equation c. the van der Waals equation d. the contravention equation e. the violation equation

60. c

7. When Dalton proposed the atomic theory, he was aware of all the following except a. the law of conservation of mass. b. the properties of cathode rays. c. the law of multiple proportions. d. the law of definite proportions

7. b

A Honda Civic Hybrid has an EPA gas mileage rating of 46 mi/gal on the highway. How many kilometers can the Civic travel on 4.0 L of gasoline? Distance traveled = 1 km Report your answer with three significant figures. Do NOT include units in your answer. 1.

8. A new element has two naturally occurring isotopes, 294X and 296X, with the following masses and natural abundances. What is its atomic mass? 294X 293.73 u 69.17% 296X 295.88 u 30.83% a. 294.39 u b. 294.67 u c. 294.88u d. 295.31 u

8. a

What is the density of a block of a metal alloy with a volume of 2.3 cm3 and a mass of 19.3 grams? Report your answer with two significant figures. Do NOT include units in your answer. Do NOT use scientific notation. density = 1 g/cm3 1.

8.4

A cube of an unknown metal, with side length of 1.32 cm, has a mass of 20.5 g. What is the density of the metal, in g/cm3? 1 g/cm3. Report your answer with three significant figures. Do NOT include units in your answer. 1.

8.91

9. What species contains 12 protons, 14 neutrons, and 10 electrons? a. 26Mg2+ b. 26Si4+ c. 24Ne2‒ d. 26Mg‒

9. a

If a reaction of FeS and HCl has a theoretical yield of 9.68 g of H2 S, what is the percent yield if only 9.04 g of H2S are recovered? 1 % Report your answer with three significant figures. Do NOT include units or the percent sign inyour answer. 1.

93.4

A 54.0 g sample of methanol absorbs 1340 J of heat, raising its temperature from 25.0°C to 35.0°C. What is the specific heat of methanol? . A. 2.48 J/(g·°C) B. 1.00 J/(g·°C) C. 248 J/(g·°C) D. 0.413 J/(g·°C)

A balloon is inflated from 0.010 L to 0.610 L against an external pressure of 2.00 atm. What is the change in internal energy of the system if there is no heat transfer? 101 J = 1.00 L•atm A. -121 J B. -1.20 J C. +121 J D. +1.20 J

A chemical reaction is performed in a flask that is sealed with a piston. The initial volume of the system is 0.550 L and after the reaction the final volume is 0.375 L. Calculate the work for the system if the external pressure is 1.00 atm. Recall that 1 L·atm = 101.3 J. A. +17.7 J B. -17.7 J C. +0.175 J D. -0.175 J

A mandarin orange provides 35 Calories, which is how many kJ of energy? 1 Cal = 4184 J A. 150 kJ B. 72 kJ C. 25 kJ D. 370 kJ

A newborn baby eats 8 times a day. If the baby eats 90. mL of formula per feeding, how many days will 850. ounces of formula last? (When mixed with water, 1 ounce = 29.6 mL.) A. 35 days B. 28 days C. 45 days D. 62 days

A sample of a compound contains 2.64 g of C, 0.444 g of H, and 3.52 g of O. What is the molecular formula of the compound if the molar mass is 60.05 g/mol? A. C2H4O2 B. C4H2O2 C. CH4O2 D. C3H6O2

An antique spoon is found to have a mass of 0.055 lbs and a volume of 2.38 cm3 using Archimedes' principle. Of what material is the spoon likely made given the densities below? Material Density (g/cm3) brass 8.55 nickel 8.91 silver 10.5 stainless steel 7.82 A. silver B. brass C. stainless steel D. nickel

At King's Island Amusement Park there is a ride called Drop Tower (see image below). Riders are lifted to the top of the tower and after some undisclosed time, they are released to freefall toward the ground. Which statement accurately describes the relative potential and kinetic energy of the riders waiting at the top of the ride? A. Kinetic energy is low (zero) and potential energy is high. B. Kinetic energy is high and potential energy is low (zero). C. Both kinetic energy and potential energy are both high. D. Both kinetic energy and potential energy are both low (zero).

Calculate the relative percent abundance of 6Li given the following information: mass of 6Li = 6.01512 amu mass of 7Li = 7.01699 amu A. 7.59 % B. 74.91 % C. 6.51 % D. 91.23 %

Choose the ground state electron configuration for Ti2+. A. [Ar]3d2 B. [Ar]4s2 C. [Ar]4s23d2 D. [Ar]4s23d4 E. [Ar]3d4

Electron affinity is the energy associated with which reaction? A. X(g) +e- →X-(g) B. X(g) →X+(g) + e- C. X-(g) →X(g) + e- D. X+(g) + e- →X(g)

Europium (Eu) has two stable isotopes, the heavier of which has a natural abundance of 52.19% and an isotopic mass of 152.92 amu. What is the mass number of the lighter isotope? A. 151 B. 154 C. 149 D. 152

For the reaction of nitrogen dioxide with water to form nitric acid and nitrogen monoxide, what is the sum of the coefficients of the balanced equation? A. 7 B. 4 C. 11 D. 9

How many grams of Li are required to produce 20.9 g of Li3N (molar mass = 34.83 g/mol) in the presence of excess oxygen according to the reaction below? 6 Li(s) + N2(g) →2 Li3N(s) . A. 12.5 g B. 31.6 g C. 2.44 g D. 8.97 g

How many grams of NaOH are required to make 250. mL of a 3.00 M solution? A. 30.0 g B. 2.78 g C. 10.2 g D. 13.3 g

How many grams of excess N2H4(l) remain after the reaction of 50.0 g of N2 O4(l) with 45.0 gof N2H4(l)? The molar mass of N2O4 is 92.02 g/mol and that of N2H4 is 32.05 g/mol. N2O4(l) + 2 N2H4(l) →3 N2(g) + 4 H2O(g) . A. 10.2 g B. 56.0 g C. 2.18 g D. 20.9 g

How many grams of oxygen can be obtained from the decomposition of 0.150 moles of potassium chlorate according to the following equation? 2 KClO3(s) →2 KCl(s) + 3 O2(g) . A. 7.20 g B. 2.40 g C. 3.40 g D. 14.4 g

The iPad Air has a height of 9.4 in. What is the height in cm? A. 24 cm B. 3.7 cm C. 61 cm D. 2.3×102 cm

Use the information provided to determine ΔH°rxn for the following reaction: CH4(g) + 4Cl2(g) → CCl4(g) + 4HCl(g) ΔH°rxn = ? . Compound ΔH°f (kJ/mol) CH4(g) -75 CCl4(g) -96 HCl(g) -92 A. -389 kJ B. -113 kJ C. +113 kJ D. +79 kJ

What are the spectator ions in the reaction of copper(II) sulfate and sodium hydroxide? A. 2 Na+, SO42- B. Cu2+, SO42- C. 2 Na+, 2 OH- D. Cu2+, 2 OH-

What is the chemical name of N2O5? . A. dinitrogen pentoxide B. nitrogen(V) oxide C. nitrogen oxide D. nitrous pentaoxide

What is the electron configuration of the most common aluminum cation? A. [Ne] B. [Ne]3s2 C. [Ne]3s23p1 D. [Ne]3s1 E. [Ne]3s23p6

What is the ground state electron configuration of molybdenum? A. [Kr]5s14d5 B. [Kr]5s24d4 C. [Kr]4d6 D. [Ar]4s13d5 E. [Ar]4s23d4

What is the longest possible wavelength of electromagnetic radiation that could eject electrons from the surface of tungsten metal, which has a work function of 7.42×10-19 J? A. 268 nm B. 594 nm C. 65.2 nm D. 1120 nm

What is the molar mass of silver nitrate? A. 169.87 g/mol B. 137.88 g/mol C. 107.87 g/mol D. 121.88 g/mol

What is the name of Fe2S3? . A. iron(III) sulfide B. iron sulfate C. iron sulfide D. diiron trisulfide

What is the reducing agent in the reaction shown below? Cd + NiO2 + 2 H2O → Cd(OH)2 + Ni(OH)2 . A. Cd B. NiO2 C. H2O D. Cd(OH)2 E. Ni(OH)2

What is the result of the calculation with the correct number of significant figures? (987.65 ×4.321) + 1234.5678 = ? A. 5502 B. 5502.2 C. 5.50 ×103 D. 5.5 ×103 E. 5.5022035 ×103

What is the result of the calculation? 4.4×102 ×0.00033 = ? A. 1.5×10-1 B. 1.5×103 C. 1.5×101 D. 1.5×10-3

What volume (in mL) of 8.0 M HCl is required to prepare 250 mL 0f 0.15 M HCl? A. 4.7 mL B. 49 mL C. 38 mL D. 30. mL

What volume of 0.235 M H2SO4 is required to completely react with 15.0 mL of 0.575 M NaOH? Hint: Start with the balanced equation. A. 18.4 mL B. 36.7 mL C. 73.4 mL D. 6.13 mL

What volume of a 0.33 M aqueous solution of C12H22O11 can be diluted with water to prepare 25 mL of a 0.025 M solution? . A. 1.9 mL B. 7.7 mL C. 17 mL D. 41 mL

When an ionic compound dissolves in water, A. the cations and anions separate and each ion is surrounded by water molecules, which is a property of strong electrolytes. B. the cations and anions separate and chemically react with the water, resulting in an oxidation-reduction reaction. C. the cations and anions remain connected to each other with their ionic bonds and the combined unit is surrounded by water molecules, which is a property of nonelectrolytes. D. the water is separated into H2 and O2 gases, which is a property of strong electrolytes

Which are examples of intensive properties? A. density and boiling point B. density and mass C. temperature and length D. color and mass

Which diatomic molecule has the shortest bond length? A. N2 B. O2 C. F2 D. Br2

Which quantum number describes the orientation of an orbital? A. magnetic quantum number B. principal quantum number C. angular momentum quantum number D. spin quantum number E. Schrödinger quantum number

Which signs on q and w represent a system that is doing work on the surroundings, as well as gaining heat from the surroundings? A. q = +, w = - B. q = -, w = + C. q = +, w = + D. q = -, w = -

Which statement is false? A. Millikan's work with charged oil droplets led to the determination of the charge of an alpha particle. B. Rutherford's interpretation of alpha particles scattering from a gold foil led to the identification of the atomic nucleus. C. Thomson's experiments with cathode rays led to the conclusion that subatomic particles exist. D. Chadwick's experiments with alpha particles and beryllium led to the identification of an uncharged subatomic particle.

You are given a container filled with an unknown liquid. Which property is most useful for identifying the substance? A. The density of the liquid is found to be 1.40 g/mL. B. The volume of liquid is 125 mL. C. The liquid is clear and colorless. D. The mass of the liquid is 175 g.

________ is the tendency of bonded electrons to be attracted to an atom. The greater the difference in the property above, the _____ polar a bond is that forms between atoms. A. Electronegativity; more B. Electronegativity; less C. Electron affinity; more D. Electron affinity; less E. Effective nuclear charge; more F. Effective nuclear charge; less

Select the two properties of a sample of water that are intensive. A. temperature B. density C. volume D. mass

A & B

Which type(s) of orbitals are able to form a sigma bond? Select all that apply. A. s B. p C. d D. f

A & B

Select the three correct classifications of aluminum. A. matter B. pure substance C. mixture D. element E. compound F. heterogeneous

A & B & D

Consider the following reaction. Select the two true statements. Mg(s) + 2 HCl(aq) →MgCl2(aq) + H2(g) . A. The reaction is an oxidation-reduction reaction. B. The reaction is a neutralization reaction. C. Magnesium is oxidized. D. Magnesium is neutralized. E. Magnesium is the oxidizing agent.

A & C

In the reaction of lithium hydroxide with hydrochloric acid, which two are the spectator ions? A. Li+(aq) B. H+(aq) C. Cl-(aq) D. OH-(aq) E. H2O(l)

A & C

The information from which two choices combined to give the mass of the electron? A. Thomson's cathode ray experiments B. Geiger, Marsden, and Rutherford's gold foil experiments C. Millikan's oil drop experiments D. Dalton's atomic theory

A & C

Which two options express correct relationships for prefix multipliers? A. 1 mL = 10-3 L B. 1 cm = 102 m C. 1 kg = 103 g D. 1 ns = 109 s

A & C

Select the two answers which correctly complete the statement: "Ionic bonds form ___" A. between a metal and a non-metal. B. between two non-metals. C. between two metals. D. due to electrostatic attractions as a result of electron transfer. E. when electrons are shared between atoms

A & D

Select the two correct statements regarding the electromagnetic spectrum. A. Wavelength increases from left to right on the spectrum. B. Wavelength decreases from left to right on the spectrum. C. Energy increases from left to right on the spectrum. D. Energy decreases from left to right on the spectrum.

A & D

Which two are physical changes? A. Ice melting. B. Decomposition of NH4Cl to NH3 and HCl. C. Rusting of iron. D. Salt dissolving in water. E. Burning gasoline.

A & D

Which two correctly pair the element with its most common ionic charge? A. Ca, 2+ B. F, 1+ C. Al, 2+ D. P, 3-

A & D

Which two have an oxidation number of zero? A. O2 B. Oxygen in the compound MnO2. C. Silver in the compound AgCl. D. Na

A & D

Which two postulates of Dalton's atomic theory were incorrect? A. Atoms are indivisible particles. B. Atoms combine in small whole-number ratios to form compounds. C. Atoms of different elements have different masses. D. All atoms of a given element have the same mass.

A & D

Which two solutions will form a precipitate after the addition of a MgCl2 solution? . A. Na2CO3 B. Ba(NO3)2 C. NH4F D. AgNO3 E. Cu(NO3)2

A & D

A 300. mL sample of H2SO4 of unknown concentration is neutralized by 272 mL of a 0.200 M NaOH during a titration. What is the concentration of H2SO4? The neutralization reaction is: H2SO4(aq) + 2 NaOH(aq) → Na2SO4(aq) + 2 H2O(l) . A. 0.200 M B. 0.0907 M C. 0.181 M D. 0.363 M

A certain oxide of manganese is 63.2% manganese. What is the formula of the oxide? A. MnO B. MnO2 C. Mn2O D. Mn2O3

A general chemistry laboratory student takes a bottle off the shelf that contains 100. mL of 0.20 M HCl. Select the true statement. A. The bottle contains 0.20 moles of HCl. B. If there were 1 L of solution, it would contain 0.20 moles of HCl. C. The bottle contains 0.20 grams of HCl. D. If there were 1 kg of solution, it would contain 0.20 grams of HCl.

A metal object with a mass of 29.5 g is heated to 97.0 °C and then transferred to an insulated container of 97.3 g of water at 20.5 °C. At thermal equilibrium, the temperature is 24.1 °C. What is the specific heat of the metal object? Assume all of the heat lost by the metal object is absorbed by the water. The specific heat of water is 4.184 J/g·°C. A. 0.054 J/g·°C B. 0.68 J/g·°C C. 0.28 J/g·°C D. 2.9 J/g·°C

A rectangular college basketball court has dimensions of 50.0 ft by 94.0 ft. What is the area of the court in m2 A. 14.3 m2 B. 437 m2 C. 1.54×104 m2 D. 928 m2

A solution of Ba(OH)2 of unknown concentration is titrated against a standard solution of 0.10 M HCl. Select the balanced neutralization equation for the reaction. . A. HCl(aq)+ Ba(OH)2(aq) →BaCl(aq) + H(OH)2(l) B. 2 HCl(aq)+ Ba(OH)2(aq) →BaCl2(aq) + 2 H2O(l) C. HCl(aq)+ Ba(OH)2(aq) →BaCl(aq) + 2 H2O(l) D. 2 HCl(aq)+ Ba(OH)2(aq) →BaCl2(aq) + 2 H2(g) + O2(g)

A substance that cannot be chemically broken down into simpler substances is A. a homogeneous mixture. B. an element. C. a heterogeneous mixture. D. a compound.

According to the first law of thermodynamics, the change in internal energy of a system can be determined by A. measuring heat transfer. B. measuring heat transfer and adding it to the work performed by or done on the system. C. determining work performed by or done on the system. D. measuring work performed by or done on the system and subtracting the heat transfer.

All atoms and ions with the same __________________ are isoelectronic. A. number of electrons B. electron configuration C. number of valence electrons D. noble gas core

An aqueous solution of Pb(NO3)2 is mixed with an aqueous solution of Al2(SO4)3. Which is the net ionic equation for the reaction, if any? . A. Pb2+(aq) + 3 SO42-(aq) →Pb(SO4)3(s) B. Pb2+(aq) + SO42-(aq) →PbSO4(s) C. 2 Al3+(aq) + 2 NO3-(aq) →Al2(NO3)2(s) D. Al3+(aq) + 3 NO3-(aq) →Al(NO3)3(s) E. No reaction.

Consider the following reaction which takes place at constant temperature and pressure. 2 NO(g) + O2(g) →2 NO2(g) If 2.0 L of NO reacts with 2.0 L of O2, how many liters of NO2 can be formed? . A. 1.0 L B. 2.0 L C. 3.0 L D. 4.0 L

Consider the reaction MnO2 + 4 HCl →MnCl2 + Cl2 + 2 H2O Calculate the theoretical yield of MnCl2 (in moles) for the reaction of 0.80 moles of MnO2 and 45 g HCl. Molar masses provided below. . Substance Molar mass (g/mol) HCl 36.46 MnO2 86.94 MnCl2 125.84 A. 0.80 mol MnCl2 B. 0.31 mol MnCl2 C. 0.19 mol MnCl2 D. 1.2 mol MnCl2 E. 1.0 mol MnCl2

Dalton's Atomic Theory states that A. an element is composed of several isotopes. B. matter is composed of small indestructible particles. C. there is a very large amount of empty space in an atom. D. that energy is neither created nor destroyed during a chemical reaction.

Determine the final temperature of a gold nugget (mass = 376 g) that starts at 125 °C and cools down by losing 4.85 kJ of heat. The specific heat capacity of gold is 0.128 J/g°C. A. 226 ºC B. 24 ºC C. 85 ºC D. 67 ºC

Electron affinity of an atom is the energy associated with the equation: A. X-(g) →X(g) + e- B. X(g) + e- →X-(g) C. X(g) →X+(g) + e- D. X+(g) + e- →X(g) E. X(aq) + e- → X-(aq)

For the isoelectronic series, which is in order of increasing (smallest to largest) size? A. F- <O2- <Mg2+ <Na+ B. Mg2+ < Na+ < F- <O2- C. O2- <F- <Na+ < Mg2+ D. Na+ < Mg2+ < O2- <F-

Gallium exists as two isotopes, 69Ga and 71Ga. The mass of 69Ga is 68.9256 with a 60.11% abundance. What is the mass of 71Ga? A. 70.520 amu B. 70.925 amu C. 69.875 amu D. 71.125 amu

How many grams of Li3N can be formed from 1.75 moles of Li? Assume an excess of nitrogen. 6 Li(s) + N2(g) → 2 Li3N(s) A. 18.3 g Li3N B. 20.3 g Li3N C. 58.3 g Li3N D. 61.0 g Li3N

How many grams of potassium iodide are in 35.5 mL of a 0.250 M solution? The molar mass of potassium iodide is 166.00 g/mol. A. 148 g B. 1.47 g C. 22.6 g D. 2.78 g

How many lone pairs (non-bonding pairs of electrons) are in the best Lewis structure for CO3 2-? . A. 5 B. 8 C. 10 D. 6

How many molecules are in 1 cup (227 g) of water? A. 6.52×10-21 molecules B. 7.59×1024 molecules C. 3.08×1018 molecules D. 4.10×1026 molecules

How many neutrons are in an atom of lead with a mass number of 208? A. 82 B. 126 C. 208 D. 290 E. none

How many significant figures are in the value, 0.00058900 ? A. 4 B. 5 C. 6 D. 7 E. 8

In a laboratory experiment, a student reacted 5 grams of one element with 10 grams of another element and collected 19 grams of a compound containing the two elements. What must be said about the student's work? A. The student was careless and lost some of the compound. There should be more than 19 grams of the compound collected. B. The student was careless and had some contaminant in the compound. There is no way 19 grams of the compound could be formed. C. The student will be famous because he discovered that a scientific law is invalid. D. The student did not understand that compounds cannot be made from elements

In examining thermodynamic tables, it is noted that the ΔH°f for NH4Cl(s) is -314.4 kJ/mol. Select the formation reaction of the compound for which this is the enthalpy change. . A. N2(g) + 4 H2(g) + Cl2(g) →2 NH4Cl(s) ΔH°=-314.4 kJ/mol B. ½N2(g) + 2 H2(g) + ½Cl2(g) →NH4Cl(s) ΔH°=-314.4 kJ/mol C. NH4Cl(s) →½N2(g) + 2 H2(g) + ½Cl2(g) ΔH°=-314.4 kJ/mol D. NH4+(aq) + Cl-(aq) →NH4Cl(s) ΔH°=-314.4 kJ/mol

Select the true statement based upon your knowledge of the DeBroglie equation, which determines the wavelength of a particle. A. The wavelength is directly proportional to the velocity of a particle. B. If velocities are held constant, wavelength is inversely proportional to mass. C. The wavelength increases as Planck's constant increases. D. The wavelength is independent of mass and velocity.

The Niagara Falls official website states that Horseshoe Falls allows 6 million cubic feet of water over the crestline every minute. A student is asked to convert 6 ×106 ft3 to cubic centimeters and gets the answer 16,990,107,955,200 cm3. While their math is correct, what is wrong with the answer? A. Nothing. If the math is correct, the answer is correct. B. It would be impossible to know the volume to the nearest 100 cm3 if it is only known to the nearest 1,000,000 ft3. C. The student should have reported the answer in scientific notation for it to be correct. D. It is not possible for the number of cm3 to be a larger number than the number of ft3.

The ionization energies (in kJ/mol) of a second period element are given below. Which element is it? IE1 = 899 IE2 = 1757 IE3 = 14850 IE4 = 21005 A. Li B. Be C. B D. C E. N

To measure a chemical property of a substance, the substance must A. remain unchanged. B. be involved in a chemical reaction. C. be a pure substance. D. undergo a physical change.

What is the change in the internal energy (ΔU) of a thermodynamic system if 1200 J of work is done on the system and it releases 31.0 kJ of heat to its surroundings? A. +31.0 kJ B. -29.8 kJ C. +32.2 kJ D. -1.2 kJ E. ΔU is unchanged

What is the chemical formula for phosphorus pentabromide? A. PB5 B. PBr5 C. P2Br10 D. BP5 E. PtBr5

What is the chemical formula of nickel(II) hydroxide? A. Ni2(OH)3 B. Ni(OH)2 C. Ni2O3 D. Ni2(H2O)2 E. NiOH

What is the ground state electron configuration of copper? A. [Ar]4s23d9 B. [Ar]4s13d10 C. [Ar]4s23d7 D. [Ar]3d10

What is the limiting reactant when 27.0 g of P and 68.0 g of I2 react according to the chemical equation below? 2 P(s) + 3 I2(s) →2 PI3(s) . A. P(s) B. I2(s) C. PI3(s) D. There is no limiting reactant is this case.

What is the mass percent of Na in Na2SO4? A. 22.57% B. 32.37% C. 16.19% D. 45.07%

What is the mass percent of potassium in K2CrO4? . A. 26.78% B. 40.27% C. 32.96% D. 28.57%

What is the percent yield of O2 in the decomposition of 126 g of KClO3 (molar mass = 122.55 g/mol) if 32.0 g of O2 are recovered? 2 KClO3(s) →2 KCl(s) + 3 O2(g) . A. 78.2% B. 64.8% C. 90.1% D. 83.7%

Which bond is the most polar? A. C-N B. C-F C. N-O D. C-P E. H-H

Which describes a pure substance in the gas phase? A. a homogeneous mixture that is able to flow and has a definite volume B. a compound that is compressible C. an element with a definite shape and volume D. a heterogeneous mixture that takes the volume of its container

Which element would you expect to have the largest increase between the 3rd and 4th ionization energies? A. He B. Al C. N D. Cl

Which one correctly pairs the metric prefix with its meaning? A. centi, 10-3 B. kilo, 103 C. deci, 10-2 D. milli, 10-6

Which one could describe the volume of a container? A. 300 g/cm2 B. 712 dm3 C. 413 m2 D. 87 kg3

Which one is a redox reaction? A. NaCl (aq)+ AgNO3(aq) →AgCl(s) + NaNO3(aq) B. 2 AgNO3(aq) + Cu(s) →Cu(NO3)2(aq) + 2 Ag(s) C. HCl(aq) + NaOH(aq) →NaCl(aq) + H2O(l) D. TiCl4(s) + H2O(g) →TiO2(s) + 4 HCl(g)

Which one is a state function? A. distance traveled B. change in internal energy C. heat D. pressure-volume work

Which pair of aqueous solutions will form a precipitate when mixed? A. NaCl and KOH B. LiCO3 and AgNO3 C. NH4Cl and CuSO4 D. Hg2(ClO4)2 and Pb(CH3COO)2

Which statement regarding the photoelectric effect is FALSE? A. There is a minimum frequency, below which no electron can be emitted. B. All electromagnetic radiation can eject an electron if the light is intense enough. C. The experiment led to the understanding that light behaves as a particle (photon). D. If the frequency of light is great enough to eject an electron, the greater the frequency, the greater the kinetic energy of the emitted electron.

Zn metal reacts with hydrochloric acid according to the balanced equation Zn(s) + 2 HCl(aq) →ZnCl2(aq) +H2(g) . When 1.00 g of Zn metal is completely reacted with 100.0 g of 0.500 M HCl(aq) in a constant-pressure calorimeter, the temperature of the solution was observed to rise from 20.30ºC to 30.50ºC. What is the change in enthalpy for the reaction (as written) per mole of Zn(s)? Use 4.18 J/g·ºC for the specific heat capacity of the solution. Assume no heat is lost to the surroundings. A. -759 kJ/mol Zn B. -282 kJ/mol Zn C. -30.4 kJ/mol Zn D. -416 kJ/mol Zn

Heisenberg's uncertainty principle can be expressed as: Δx x mΔv >/- h/4pi where Δx is the uncertainty in the position, and Δv is the uncertainty in the velocity of an object. Select the two true statements which follow from the uncertainty principle. A. The more certainty we have in the position of a particle, the more certainty we have in its velocity. B. The more certainty we have in the position of a particle, the less certainty we have in its velocity. C. If we know precisely the position of a particle, we know nothing about its velocity. D. If we know precisely the position of a particle, we also know precisely its velocity.

B & C

Select the two answers that show the same number in both scientific and standard notation. A. 1,200,000; 1.2 ×10-6 B. 426; 4.26 ×102 C. 0.000045; 4.5 ×10-5 D. 0.010; 1.0 ×102

B & C

Which two of the following reactions will produce a precipitate? A. HBr(aq) + NaOH(aq) → B. NaI(aq) + AgNO3(aq) → C. Pb(C2H3O2)2(aq) + 2LiBr(aq) → D. Ba(NO3)2(aq) + 2HCl(aq) →

B & C

Which two represent exact numbers? A. 1 L = 1.06 quarts B. 1 in = 2.54 cm C. 256 students in a classroom D. 75.9% exam average E. 591 mL of soda per bottle

B & C

Select the two problems below that are limiting reactant problems. A. Calculate the volume of 0.25 M NaOH required to react completely with 35 mL of 0.12 M HCl. B. Calculate the grams of AgCl are formed if 0.250 g NaCl is added to 75.0 mL of 0.10 M AgNO3. C. Calculate the molarity of a solution formed when 55.0 mL of H2O is added to 45.0 mL of 0.25 M Ba(OH)2. D. Calculate the grams of NO formed if 0.015 moles of N2 reacts with 1.4 g O2 according to the reaction N2 + O2 →2 NO.

B & D

Select the two transition metals from the list below: A. magnesium B. copper C. lead D. gold E. barium

B & D

Which two compounds are insoluble? A. AgNO3 B. CoCO3 C. CaCl2 D. PbS E. Na2SO4

B & D

Which two of the pure substances below are molecular elements? A. argon B. bromine C. carbon dioxide D. oxygen E. lithium

B & D

A solution of silver nitrate, AgNO3 is added to a solution of calcium chloride, CaCl2. What is the net ionic equation of the reaction? . A. Ag+(aq) + Cl2-(aq) →AgCl2(s) B. Ag+(aq) + 2Cl-(aq) →AgCl2(s) C. Ag+(aq) + Cl-(aq) →AgCl(s) D. Ca2+(aq) + NO3-(aq) →CaNO3(s) E. Ca2+(aq) + 2 NO3-(aq) →Ca(NO3)2(s) F. Ca(aq) + Ag(aq) →CaAg(s)

After some fact or facts have been observed, a scientist would like to find an explanation for what is observed. What is the next step of the scientific method? A. A law is established that is an explanation of the fact(s). B. An experiment is designed to explain the fact(s). C. A hypothesis is proposed as an initial explanation of the fact(s). D. A theory is adopted which explains the fact(s).

Bromine is in the same group as ____, and the same period as ____. A. selenium, fluorine B. krypton, iron C. chlorine, potassium D. iodine, oxygen

Calculate ΔHrxn for the reaction: Cu(s) + ½O2(g) → CuO(s) given, . 2 Cu(s) + S(s) → Cu2S(s) ΔH = -75.9 kJ S(s) + O2(g) → SO2(g) ΔH = -297 kJ Cu2S(s) + 2 O2(g) → 2 CuO(s) + SO2(g) ΔH = -528 kJ A. -35.1 kJ/mol B. -66.1 kJ/mol C. -153 kJ/mol D. -314 kJ/mol

Consider the process below with a missing symbol M(g) + e- →____(g) Select the answer that provides the missing symbol and the name of the energy associated with the process. A. M+; ionization energy B. M+; electron affinity C. M-; ionization energy D. M-; electron affinity

Consider the reaction: 3 H2(g) + N2(g) → 2 NH3(g) How many moles of N2 are required to completely react with 0.450 moles of H2? . A. 0.450 mol B. 1.00 mol C. 0.150 mol D. 1.35 mol

Consider the results of three students who repeatedly weighed a lead block known to have a true mass of 10.00 g. . Student A Student B Student C Trial 1 10.49 g 9.78 g 10.03 g Trial 2 9.79 g 9.82 g 9.99 g trial 3 9.92 g 9.75 g 10.03 g Trial 4 10.31 g 9.80 g 9.98 g Average 10.13 g 9.79 g 10.01 g Which student's data is considered both accurate and precise? A. Student A B. Student B C. Student C D. All data is accurate and precise.

Determine the molarity of a solution containing 13.9 g of CaCl2 in 2.75 L of solution. . A. 5.05 M B. 22.1 M C. 0.0455 M D. 0.291 M

Energy that is associated with the position or composition of an object is called A. kinetic energy. B. thermal energy. C. potential energy. D. electromagnetic energy

Examine the following electron configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p4 Select the electron configuration that is for a ground state atom in the same group (family). A. 1s2 2s2 2p6 3s2 3p6 4s24d10 4p4 B. 1s2 2s2 2p6 3s2 3p6 C. 1s2 2s2 2p6 3s2 3p4 D. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6

How many kJ of heat are produced by the combustion of 24.3 g of benzene (C6H6, molar mass: 78.114 g/mol)? 2 C6H 6 (l) + 15 O 2(g) →12 CO2(g) + 6 H2O(g) ΔH°rxn = -6278 kJ A. 0.302 kJ B. 3190 kJ C. 976 kJ D. 40.1 kJ

How many liters of wine can a wine barrel with a capacity of 26.0 gallons hold? 1 gallon = 4 quarts, 1.06 quarts = 1 liter A. 1.46 × 10-4 L B. 0.146 L C. 98.1 L D. 6.87 × 103 L E. 6.87 L

How many moles of chromium are produced by the reaction of 40.0 g of Cr2O3 (molar mass = 151.989 g/mol) with 8.00 g of aluminum? 2 Al + Cr2O3 → Al2O3 + 2 Cr . A. 0.388 mol Cr B. 1.24 mol Cr C. 0.296 mol Cr D. 0.773 mol Cr

How many protons (p), neutrons (n), and electrons (e) are in a neutral 116Sn atom? A. p = 66, n = 50, e = 66 B. p = 50, n = 66, e = 66 C. p = 50, n = 66, e = 50 D. p = 50, n = 66, e = 116 E. p = 66, n = 116, e = 116

If 23.0 g of Na metal react with 35.5 g of Cl gas, how many grams of NaCl form? A. 12.5 g B. 23.0 g C. 58.5 g D. 35.5 g

In a titration, 34.62 mL of 0.1510 M NaOH are needed to neutralize 50.0 mL of an H2SO4 solution. What is the concentration of the sulfuric acid solution? . A. 0.0229 M H2SO4 B. 0.281 M H2SO4 C. 0.0523 M H2SO4 D. 0.105 M H2SO4

In alcohol fermentation, yeast converts glucose, C6H12O6,to ethanol, C2H5OH, and carbon dioxide: C6H12O6(s) →2 C2H5OH(l) + 2 CO2(g) Starting with 5.97 g of glucose, what is the theoretical yield of carbon dioxide in liters, collected at 293 K and 0.984 atm? Substance Molar mass (g/mol) C6H12O6 180.18 C2H5OH 46.08 CO2 44.01 A. 0.449 L B. 0.812 L C. 1.62 L D. 176 L

In the process of producing a silver dollar coin containing 31.1 g of pure silver, the metal is heated to 962°C. How much heat must be given off for the coin to return to room temperature, 20.0°C? The specific heat of silver is 0.24 J/g·°C. A. 85 kJ B. 2.4 kJ C. 7.0 kJ D. 31 kJ

In the scientific method, an explanation that has been tested and verified is a(an) A. observation. B. hypothesis. C. theory. D. law.

Liquid hexane, C6H14 (molar mass = 86.178 g/mol), has a density of 0.6548 g/mL at room temperature. What volume of hexane contains 5.33 × 1022 molecules? . A. 8.59 mL B. 13.5 mL C. 11.6 mL D. 7.40 mL

Rank the following elements in order of increasing (smallest to largest) ionization energies: Na, Cl, N, Rb. A. Na <Cl <N <Rb B. Rb <N < Cl <Na C. Rb <Na <Cl <N D. N <Cl <Na <Rb

Select the most electronegative element. A. C B. Ge C. O D. Se

The air in a bicycle tire is bubbled through water and collected. If the total volume of gas collected (after moisture is removed) is 5.45 L at 25 ºC and a pressure of 745 torr, how many moles of gas were in the bicycle tire? A. 1.94 ×103 mol B. 2.63 mol C. 0.218 mol D. 0.750 mol

The average U.S. farm occupies 435 acres. If 1 acre = 43560 ft2, how many square kilometers is this? A. 5.77 × 103 km2 B. 0.680 km2 C. 1.76 km2 D. 2.25 × 102 km2

The density of titanium metal is 4.51 g/cm3. What is the volume of a 1.00 kg sample of Ti? A. 10.9 cm3 B. 9.17×104 cm3 C. 222 cm3 D. 4.51×10-1 cm3

The effective nuclear charge is A. equal to the number of protons in the nucleus. B. the charge of a cation on anion. C. the nuclear charge felt by an electron. D. the attraction of bonded electrons to an atom.

The manufacturing specifications of a metal rod used in a general chemistry lab was determined to be 6.550 cm. Students in the lab were asked to measure the length of the rod by whatever means they had at their disposal. Which set of data is very precise, but not accurate? A. 6.0 cm, 6.2 cm, 6.6 cm, 6.1 cm B. 6.551 cm, 6.498 cm, 6.552 cm, 6.551 cm C. 7.446 cm, 7.450 cm, 7.448 cm, 7.449 cm D. 5.2 cm, 6.6 cm, 5.3 cm, 4.8 cm

The mass of an atom is determined by its number of ______; the charge of an atom is determined by its number of ______. A. protons; electrons B. neutrons; protons and electrons C. protons and neutrons; protons and electrons D. electrons; electrons E. electrons and neutrons; neutrons and protons

Two or more substances in variable proportions, where the composition is variable throughout, are A. elements. B. a homogeneous mixture. C. a heterogeneous mixture. D. compounds.

What answer should be reported, with the correct number of significant figures, for the following calculation? 96.34 × 11.135 × 2.67/230.597 = ? A. 12.420 B. 12.42 C. 12.4 D. 12

What is the chemical formula for sodium nitrate? A. Na3N B. Na(NO2)2 C. NaNO3 D. Na2NO3 E. Na(NO3)2

What is the de Broglie wavelength (in nm) of a beta particle (mass = 9.11 ×10-31 kg) traveling at the speed of light? A. 8.82 ×10-3 nm B. 1.08 ×10-3 nm C. 2.42 ×10-3 nm D. 3.42 ×1038 nm

What is the electron configuration of Ag+? A. [Kr]4s13d9 B. [Kr]4s13d10 C. [Kr]3d10 D. [Kr]4s23d8

What is the electron geometry of PCl5? A. octahedral B. tetrahedral C. trigonal bipyramidal D. square pyramidal

What is the formula of the ionic compound formed between the most common ions of silver and sulfur? A. AgS B. Ag2S3 C. Ag2S D. AgS2

What is the molarity of the final solution when 255 mL of water are added to 0.550 L of a 2.50 M sodium chloride solution? A. 5.39 M B. 1.16 M C. 1.71 M D. 5.50×10-3 M

What is the oxidation state of carbon in HCO3 -? . A. -2 B. +6 C. +4 D. -1 E. +2

Which are equivalent? A. 102 cm and 10-2 m B. 50 K and -323°C C. 500 Mg and 5×108 g D. 3000 μs and 3×1012 ps

Which element in period two should have the following trend in ionization energies (kJ/mol)? IE1=1,400 IE2=2,860 IE3=4,580 IE4=7,500 IE5=9,400 IE6=53,000 . A. carbon B. lithium C. nitrogen D. fluorine

Which number has the fewest significant figures? A. 0.5500 B. 9.2 × 101 C. 0.0000707 D. 9.031

Which one is NOT a strong acid? A. H2SO4 B. HCl C. HF D. HI

Which one is a precipitation reaction? A. C3H8(g) + 5 O2(g) →3 CO2(g) + 4 H2O(l) B. NaHCO3(aq) + HCl(aq) →NaCl(aq) + H2O(l) +CO2(g) C. 2 NaI(aq) + Pb(NO3)2(aq) →2 NaNO3(aq) + PbI2(s) D. HCl(aq) + NaOH(aq) →NaCl(aq) + H2O(l)

Which one represents a possible molecular formula for the empirical formula of C3H5ClO? . A. C6H10ClO2 B. C5H10Cl2O2 C. C6H10Cl2O2 D. C6H12Cl2O2

Which reaction represents ΔH°f, the standard enthalpy of formation, for CH4? . A. CH4(g) →C(s) + 2 H2(g) B. C(s) + 4 H(g) →CH4(g) C. C(s) + 2 H2(g) →CH4(g) D. 2C(s) + 4 H2(g) →2 CH4(g) E. Both c) and d)

Which set of quantum numbers cannot occur together to specify an orbital? A. n = 2; l = 1; ml= -1 B. n = 3; l = 2; ml= 0 C. n = 3; l = 3; ml= 2 D. n = 4; l = 3; ml = -3

Which set of quantum numbers is not allowed? A. n = 4, l = 2, ml = 1, ms = +½ B. n = 1, l = 0, ml = 0, ms = -½ C. n = 3, l = 2, ml = 3, ms = +½ D. n = 2, l = 1, ml = -1, ms = -½

Which statement best describes an exothermic reaction? A. negative ΔH, absorbs heat from the surroundings, and feels cold to the touch. B. positive ΔH, gives off heat to the surroundings, and feels warm to the touch. C. negative ΔH, gives off heat to the surroundings, and feels warm to the touch. D. positive ΔH, absorbs heat from the surroundings, and feels cold to the touch.

Which statement is false? A. Potential energy is associated with the position or composition of an object. B. Kinetic energy is associated with the motion of an of an object. C. Chemical energy is created during a chemical reaction. D. Thermal energy is associated with molecular motion

Which statement is false? A. Thermal energy is a type of kinetic energy. B. Potential energy is stored energy. C. Energy cannot be converted from potential to kinetic energy. D. Energy can be neither created nor destroyed in a process.

Select the two species that are isoelectronic. You must select both correct species to receive credit for this question. A. Ca B. Sr C. Sr2+ D. Kr E. Zr2+

C & D

When John Dalton proposed his atomic theory in 1805, he postulated that all matter is made of atoms that are indivisible, and that atoms of the same element have exactly the same mass. Which two statements suggest that this is not exactly correct? A. We now know that bonds between atoms may be broken in chemical reactions. B. We now know that mass is always conserved in a chemical reaction. C. We now know that isotopes exist. D. We now know that atoms are made of protons, neutrons, and electrons

C & D

Which two compounds are soluble in water? A. Cu3(PO4)2 B. FeS C. Cu(NO3)2 D. SrCO3 E. Ba(OH)2

C & E

A 3.111 g sample of gas in a 0.526 L vessel exerts a pressure of 1.50 atm at 318 K. What is the molar mass of the gas? A. 92.4 g/mol B. 13.1 g/mol C. 44.3 g/mol D. 103 g/mol

A compound contains 52.14% carbon, 34.73% oxygen, and hydrogen. What is the empirical formula of the compound? A. CHO B. CH3O C. C4H13O3 D. C2H6O

According to the following reaction, what amount of Al2S3 remains when 20.00 g of Al2S3 react with 2.00 g of H2O? Al2S3 = 150.17 g/mol, H2O = 18.02 g/mol. Al2S3(s) + 6H2O(l) → 2Al(OH)3(s) + 3H2S(g) . A. 2.75 g B. 14.00 g C. 8.33 g D. 17.22 g

An American dollar coin contains 7.17 g of copper. How many moles of copper are in the coin? A. 0.122 moles B. 0.179 moles C. 0.0635 moles D. 0.113 moles

Calculate the frequency of the green light emitted by a hydrogen atom with a wavelength of 486.1 nm. A. 3.46 ×1014 s-1 B. 7.86 ×1014 s-1 C. 4.33 ×1014 s-1 D. 6.17 ×1014 s-1

Calculate the lattice enthalpy, ΔHlattice, of magnesium fluoride, MgF2, using the Born-Haber cycle and the information given below. ΔHf° of MgF2(s) -1123 kJ/mol Enthalpy of sublimation of Mg(s), ΔHsub° 148 kJ/mol 1st ionization energy (IE) of Mg(g) 738 kJ/mol 2nd ionization energy (IE) of Mg(g) 1450 kJ/mol Bond dissociation energy (BE) of F2(g) 159 kJ/mol 1st electron affinity (EA) of F(g) -328 kJ/mol A. -716 kJ/mol B. -2521 kJ/mol C. -1044 kJ/mol D. -2962 kJ/mo

Calculate the moles of AgCl formed if 0.250 g NaCl is added to 75.0 mL of 0.100 M AgNO3. AgNO3(aq) + NaCl(aq) →AgCl(s) + NaNO3(aq) . A. 0.00625 mol B. 0.0119 mol C. 0.00750 mol D. 0.00428 mol

Copper has two stable isotopes, 65Cu and 63Cu. If 63Cu has a natural abundance of 69.15% and an isotopic mass of 62.9296 u, what is the isotopic mass of 65Cu? A. 63.55 u B. 65.11 u C. 64.79 u D. 64.93 u

Define bond energy. A. Energy required to form 1 mole of the bond in the solid phase. B. Energy required to form 1 mole of the bond in the gas phase. C. Energy required to break 1 mole of the bond in the liquid phase. D. Energy required to break 1 mole of the bond in the gas phase. E. Energy required to break 1 mole of the bond in the solid phase.

Determine the energy change associated with the transition from n=3 to n=2 in the hydrogen atom. A. +3.03 ×10-19 J B. -1.82 ×10-19 J C. +1.82 ×10-19 J D. -3.03 ×10-19 J

For the quantity measured, which option gives the correct SI base unit and abbreviation? A. Weight is measured in grams (gm). B. Length is measured in kilometers (Km). C. Time is measured in milliseconds (μs). D. Temperature is measured in kelvins (K).

Household hydrogen peroxide is an aqueous solution containing 3.0% H2O2 by mass. What is the molality of H2O2 in this solution? . A. 9.1 ×10-4 m B. 0.031 m C. 8.8 ×10-4 m D. 0.91 m

How many atoms of nitrogen are in 15 grams of calcium nitrate, Ca(NO3)2? A. 2.0 atoms B. 9.0 atoms C. 5.4 ×1022 atoms D. 1.1 ×1023 atoms

How many total atoms are in 7.30 g of CH4? . A. 4.11 × 1025 atoms B. 7.30 × 1023 atoms C. 1.61 × 1023 atoms D. 1.37 × 1024 atoms E. 9.73 × 1023 atoms

If the empirical formula of a compound is C9H18O and its molar mass is 284.5 g/mol, what is its molecular formula? . A. C10H6O B. C16H28O4 C. C20H12O2 D. C18H36O2 E. C36H72O4

Select the reaction in which sodium is reduced. A. NaOH(aq) + HCl(aq) →NaCl(aq) + H2O(l) B. NaCl(aq) + AgNO3(aq) →NaNO3(aq) + AgCl(s) C. Na(s) + H2O(l) →NaOH(aq) + ½H2(g) D. NaCl(l) →Na(s) + ½Cl2(g)

What is the electron configuration of a neutral silver atom in its ground state? A. [Kr]5s24d9 B. [Kr]5s24d10 C. [Kr]5s14d9 D. [Kr]5s14d10

What is the estimated effective nuclear charge on a valence electron in a neutral silicon atom? A. 0 B. +1 C. +2 D. +4

What is the molarity of a solution formed by dissolving 0.475 g of NaCl in enough water to yield 25.0 mL of solution? The molar mass of NaCl = 58.44 g/mol. A. 0.00815 M B. 0.00325 M C. 0.255 M D. 0.325 M

What is the name of Co2(SO4)3 ? A. cobalt sulfite B. dicobalt sulfate C. dicobalt trisulfide D. cobalt(III) sulfate

What is the name of N2O5? A. nitrogen oxide B. nitrogen(II) oxide C. nitrogen pentoxide D. dinitrogen pentoxide

What is the name of Na2SO4? A. sodium sulfite B. sodium(II) sulfate C. sodium(I) sulfate D. sodium sulfate

What is ΔH°rxn? CH4(g) + 4 Cl2(g) →CCl4(g) + 4 HCl(g) . Compound ΔH°f (kJ/mol) CH4(g) -75 CCl4(g) -96 HCl(g) -92 . A. 79 kJ B. -584 kJ C. -127 kJ D. -389 kJ

Which compound contains both ionic bonds and covalent bonds? A. C 8 H18 B. GeO2 C. FeBr3 D. K2CO3

Which electrons in the ground-state of a neutral magnesium atom experience the greatest amount of shielding? A. 1s electrons B. 2s electrons C. 2p electrons D. 3s electrons E. 3p electrons

Which element is classified as a metalloid? A. scandium B. sulfur C. cesium D. antimony

Which ion is permanganate? A. ClO4- B. MgO4- C. MgO42- D. MnO4- E. MnO42-

Which is not an empirical formula? A. C5H12 B. K2Cr2O7 C. C6H10O3 D. H2C2O4

Which one is NOT a unit of volume? A. liter, L B. cubic meter, m3 C. gallon, gal D. gram, g

Which one is a redox reaction? A. HBr(aq) + NaOH(aq) →NaBr(aq) + H2O(l) B. NaI(aq) + AgNO3(aq) →AgI(s) + NaNO3(aq) C. Pb(C2H3O2)2(aq) + 2LiBr(aq) →PbBr2(s) + 2LiC2H3O2(aq) D. Ba(s) + 2HCl(aq) →BaCl2(aq) + H2(g)

Which one is a weak electrolyte in aqueous solution? A. H2SO4 B. N2 C. NaCl D. HC2H3O2 (acetic acid) E. C6H12O6 (glucose)

Which one is an acid-base reaction? A. Zn(s) + 2 AgClO3(aq) →Zn(ClO3)2(aq) + 2 Ag(s) B. CuBr2(aq) + 2 NH4OH(aq) →Cu(OH)2(s) +2 NH4Br(aq) C. NaCl(aq) + LiBr(aq) →NaBr(aq) + LiCl(aq) D. H2SO4(aq) + Ba(OH)2(aq) →BaSO4(s) + 2 H2O(l)

Which option lists the elements in order of increasing metallic character? A. Ba <K <Mg <Na B. K <Mg <Na <Ba C. Ba <K <Mg <Na D. Na <Mg <K <Ba

Which set of quantum numbers represents a valence electron in a neutral calcium atom? A. [3, 0, 0, +½] B. [4, 1, 1, +½] C. [3, 2, 1, +½] D. [4, 0, 0, +½]

Which statement about quantum numbers and orbitals is true? A. The size of the orbital decreases with increasing principal quantum number, n. B. The direction in which the orbital rotates is determined by the principal quantum number, n. C. The size of the orbital dependent of the magnetic quantum number, ml. D. The shape of the orbital is determined by the angular momentum quantum number, l.

Which statement concerning quantum numbers is false? A. Multiple electrons in the same atom can share the same value for the principal quantum number. B. Multiple electrons in the same atom can share the same values for the principal and angular momentum quantum numbers. C. Multiple electrons in the same atom can share the same values for the principal, angular momentum, and magnetic quantum numbers. D. Multiple electrons in the same atom can share the same values for the principal, angular momentum, magnetic, and spin quantum numbers

Which transition in a hydrogen atom will release a photon with the shortest wavelength? A. n = 2 to n=1 B. n= 3 to n =2 C. n= 4 to n= 3 D. n = 4 to n= 1

"All samples of a given compound, regardless of their source or how they were prepared, have the same proportions of their constituent elements" is a statement of the law of A. diminishing returns. B. conservation of energy. C. conservation of mass. D. multiple proportions. E. definite proportions.

Atoms of the same element with different mass numbers are called A. ions. B. neutrons. C. allotropes. D. chemical families. E. isotopes.

How many non-bonding electrons are on the xenon atom in the proper Lewis structure of xenon tetrafluoride, XeF4? . A. one non-bonding electron B. two non-bonding electrons (one lone pair) C. zero non-bonding electrons D. three non-bonding electrons E. four non-bonding electrons (two lone pairs)

Upon absorbing 100.0 J of heat, the increase in temperature would be greatest for which substance? A. 10.0 g of Ag, Cs,Ag = 0.235 J/(g·°C) B. 10.0 g of H2O, Cs,H2O = 4.18 J/(g·°C) C. 10.0 g of ethanol, Cs,ethanol = 2.42 J/(g·°C) D. 10.0 g of Fe, Cs,Fe = 0.449 J/(g·°C) E. 10.0 g of Au, Cs,Au = 0.128 J/(g·°C)

What is the change in internal energy for a system which loses 422 J of heat, and on which 227 J of work is done? A. +649 J B. -649 J C. 0 J D. +195 J E. -195 J

Which one is a lanthanide (or rare earth) element? A. Hg B. Fe C. W D. S E. Sm

A compound is 61.7% germanium, 30.6% carbon and 7.7% hydrogen by mass. Put symbols in order of GeCH. Enter the formula without subscripting the numbers, add no spaces, and use parentheses if needed, e.g., C4H4O2 or (NH4)2S. Its empirical formula is 1 . 1.

GeC3H9

Give the chemical formula of one of the binary strong acids. A binary compound is one which contains only two elements. Formula: 1 1.

HCl|HBr|HI|

What is the chemical formula of sulfur hexafluoride? Enter the formula without subscripts or spaces. Use parentheses if needed, e.g., C4H4O2 or (NH4)2S. 1 1.

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