Chem 121 Final

A mole ratio is the ratio between the number of moles of any two species involved in the chemical reaction. a. True b. False

A

A mole ratio is used to convert the given number of moles of one substance to the unknown number of moles of a second substance. a. True b. False

A

A pressure of 414 torr is equal to a. 0.545 atm b. 1.52 atm c. 1.84 atm d. 0.659 atm

A

A solution is prepared by mixing 20.0 mL of methanol with enough water to produce 400.0 mL of solution. What is the volume percent of methanol in this solution? a. 5.00 % b. 5.26 % c. 0.500 % d. 4.76 %

A

Combining hydrogen gas and oxygen gas to form water is a A. chemical change. B. physical change. C. conservation reaction. D. none of these choices

A

For the reaction: N2 + 3H2 2NH3. Which of the following is the limiting reactant if 78 g of N2 and 26 g of H2 are combined? (Molar mass: N2 28.0 g, H2 2.0 g, NH3 17.0 g) a. N2 b. H2 c. NH3 d. None of these choices.

A

In a ___ solution, the dissolved solute is in equilibrium with the undissolved solute. a. saturated b. supersaturated c. unsaturated

A

In which direction will the equilibrium shift when temperature is increased in the following equilibrium? 2 SO3 (g) + 188 kJ 2 SO2 (g) + O2 (g) a. shift to the right b. shift to the left c. no shift

A

In which direction will the equilibrium shift when volume is decreased in the following equilibrium? 2 NO (g) + O2 (g) 2 NO2 (g) a. shift to the right b. shift to the left c. no shift

A

The electron configuration, [Ar] 4s 1 , is the ground state electron configuration of a. potassium. b. sodium. c. phosphorous. d. fluorine.

A

The high boiling point of water is due to a. hydrogen bonds. b. polar covalent bonds. c. nonpolar covalent bonds. d. ionic bonds.

A

The limiting reactant in a chemical reaction is the reactant which is completely consumed. a. True b. False

A

The mass of H2SO4 (molar mass 98 g/mol) in 400. mL of 0.100 M solution is a. 3.92 g b. 4.90 g c. 9.80 g d. 2.45 g

A

The maximum number of electrons that can fit into a single d orbital is a. 2. b. 6. c. 10. d. 14.

A

The mole is 6.022 x 1023 particles. a. True b. False

A

The products of an acid plus a base are a salt and water. a. True b. False

A

What is the empirical formula of a compound that consists of 39.99% carbon, 6.73% hydrogen, and 53.28% oxygen? a. CH2O b. C2HO c. CHO d. CHO2

A

What mass of KCl is dissolved in 250. mL of a solution that is 4.00 % by mass/volume? a. 10.0 g b. 40.0 g c. 100. g d. 4.00 g

A

What volume of oxygen is consumed when 3.00 mol of carbon monoxide is produced in the following equation at STP? 2 C(s) + O2(g) 2 CO(g) a. 33.6 L b. 22.4 L c. 67.2 L d. 1.50 L

A

When the equation NH4OH + H2SO4 (NH4)2SO4 + H2O is balanced, a term in the balanced equation is a. 2H2O b. 2(NH4)2SO4 c. NH4OH d. 2H2SO4

A

Which Keq value indicates the reaction goes farthest to completion (most products) assuming similar stoichiometry? a. 1.0 × 102 b. 1.4 × 10-2 c. 1 d. 10

A

Which is the formula of iron(II) nitrate? A. Fe(NO3)2 B. Fe3NO3 C. Fe2NO3 D. FeNO3

A

Which of the following is one of the conjugate acid base pairs in the following equation? H2SO4 + H2O → HSO4 - + H3O+ a. H2SO4 and HSO4 - b. H2SO4 and H2O c. HSO4 - and H3O+ d. H3O+ and H2SO4

A

Which of the following is the formula for dinitrogen tetroxide? A. N2O4 B. N4O2 C. N2O D. NO2

A

Which of the following substances would exhibit hydrogen bonding? a. HHH-C-C--O -O-H b. c. d.

A

Which shows a balanced chemical equation for the complete combustion of methane (CH4) gas? a. CH4 + 2O2 CO2 + 2H2O b. CH4 CO2 + 2O2 + H2O c. CO2 + H2O CH4 + 2O2 d. 2CH4 + 3O2 2CO + 4H2O

A

Which state of matter consists of particles held together firmly but not rigidly? These particles are held together by strong attractive forces, are in close contact with one another, but are able to flow by one another. A. liquid B. gas C. solid D. vapoR

A

The total number of molecules contained in 22.4 L of nitrogen gas at STP is ___. a. 6.023 × 10-23 molecules b. 22.4 molecules c. 6.023 × 1023 molecules d. 1 molecule

C

What is the molarity of a solution in which 1.20 mol of solute is dissolved in 3.00 L of solution? a. 360. M b. 3.60 M c. 0.400 M d. 15.0 M

C

What is the pH in a 0.0001 M solution of LiOH? a. 1.0 × 10-11 b. 3.0 c. 10.0 d. 1.0 ×10-3

C

What is the percent water in MgSO4•7H2O? a. 0.488 % b. 2.05 % c. 51.2 % d. 48.8 %

C

What subatomic particles contribute to the charge of the atom? A. proton and neutron B. neutron and electron C. electron and proton D. proton, electron, and neutron

C

Which element forms a diatomic molecule? A. Neon B. Calcium C. Chlorine D. Sulfur

C

Which of the following is a strong base? a. HCl b. NH3 c. KOH d. CH3OH

C

Which of the following reactants would you add to an aqueous solution of silver nitrate in order to precipitate quantitatively all the silver? a. KF b. NaNO3 c. NaCl d. H2O

C

The hydronium ion is responsible for the properties of a. salts. b. bases. c. acids.

C

A tentative explanation of certain facts that provides the basis for further experimentation is a(n) ___. A. observation B. hypothesis C. law D. theory

B

As the attractive forces between the molecules of a liquid increase, its equilibrium vapor pressure at a given temperature. a. increases. b. decreases. c. remains the same.

B

Atoms of which element has the following electron configuration? 1s 2 2s 2 2p 6 3s 2 3p 3 a. nitrogen b. phosphorus c. sulfur d. argon

B

Brønsted and Lowry defined an acid as a(n) a. proton acceptor. b. proton donor. c. electron donor. d. electron acceptor.

B

Calculate the value of Keq for the following equilibrium when [PCl5] = 0.010 M, [PCl3] = 0.020 M, and [Cl2] =0.020 M. PCl5 (g) PCl3 (g) + Cl2 (g) a. 0.0219 b. 0.040 c. 29.7 d. 0.0337

B

HClO is named? A. chloric acid. B. hypochlorous acid. C. perchloric acid. D. chlorous acid.

B

How many molecules are present in 4.00 mol of Cl2? a. 2.84 x 1025 molecules b. 2.41 x 1024 molecules c. 1.51 x 1023 molecules d. 7.09 x 1024 molecules

B

How many moles of iron(III) oxide are required to completely react with 0.0232 moles of carbon in the following reaction? Fe2O3 + 3C 2Fe + 3CO a. 0.0232 mol b. 0.00773 mol c. 0.0696 mol d. 4.67 × 1021 mol

B

How many orbitals are contained in the 3d sublevel? a. 2 b. 5 c. 7 d. 10

B

If you travel to Canada, speed limits are posted in km/hr. For a speed limit of 70. mi/hr, what would be the speed limit posted on a Canadian highway? (1 mile = 1.609 km) A. 72 km/hr B. 110 km/hr C. 44 km/hr D. 68 km/hr

B

In an acidic solution the a. concentration of hydronium ion and hydroxide ion are equal. b. concentration of hydronium ion is greater than that of hydroxide ion. c. concentration of hydroxide ion greater than that of hydronium ion.

B

In the reaction 3Ag(s) + 4HNO3(aq) → 3AgNO3(aq) + NO(g) + 2H2O(l) The reactants are: A. AgNO3(aq), NO(g) B. Ag(s), HNO3(aq) C. HNO3(aq), H2O(l) D. AgNO3(aq), NO(g), H2O(l)

B

One mole of glucose, C6H12O6, contains 24 atoms. a. True b. False

B

Question 25 Hydrocyanic acid, HCN, is a weak acid whose Ka value is 4.0 × 10-10. What is the [H3O+] in a 0.10 M solution of HCN? HCN(aq) + H2O ⇌ H3O+(aq) + CN(aq) a. 1 × 10-4 b. 6.3 × 10-6 c. 4.0 × 10-9 d. 1.0 × 10-11

B

In the following reaction, CH3NH2 + H2O ⇌ CH3NH3 + + OHthe compound CH3NH2 behaves as: a. a conjugate acid. b. an acid. c. a base. d. a salt.

C

The element with atomic number 53 is ___. A. indium B. iron C. iodine D. iridium

C

The concentration of an aqueous solution of iron(II) chloride (FeCl2) is 0.0550 M. What is the molarity of each ion in this solution? FeCl2(s) ⟶ Fe2+(aq) + 2Cl-(aq) 0.0550 M 0.0550M + 0.110M a. 0.0550 M for both the iron(II) and chloride ions. b. 0.0550 M for the iron(II) ion and 0.110 M for the chloride ion. c. 0.110 M for the iron(II) ion and 0.0550 M for the chloride ion. d. not enough information is given to determine each molarity.

B

The distance between two consecutive wave peaks is known as a. frequency. b. wavelength. c. amplitude.

B

The following reaction: Mg + FeO MgO + Fe, is an example of a. combination. b. single-displacement. c. double-displacement. d. decomposition.

B

The mass of a copper atom is 1.045 × 10 -22 g. How many copper atoms are present in a 94.5 g sample of copper? A. 94.5 B. 9.04 × 10 23 C. 1.045 × 10 -22 D. 1870

B

The reaction: 2C2H6 + 7O2 4CO2 + 6H2O + 890.4 kJ, is a isothermic. b. exothermic. c. endothermic. d. protothermic.

B

The temperature of 295 K is equal to which Fahrenheit temperature? A. 32 °F B. 72 °F C. 44 °F D. 41 °F

B

What are the spectator ions when hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH)? a. H + and OH - b. Na + and Cl - c. Na + and H + d. Cl - and OH -

B

What is the concentration of an HCl solution if 12.1 mL of the solution is neutralized by 11.0 mL of a 0.31 M NaOH solution? a. 0.75 M b. 0.28 M c. 0.40 M d. 0.34 M

B

What is the mass of 0.724 moles of carbon tetrachloride (the molar mass of CCl4 153.8 g) ? a. 212 g b. 111 g c. 154 g d. 312 g

B

What is the molarity of the resulting solution when 300. mL of a 0.400 M solution is diluted to 800. mL? a. 0.109 M b. 0.150 M c. 1.47 M d. 1.07 M

B

What is the molecular formula of a compound with the empirical formula CH2Cl and molar mass of 98.96 g? a. C3H6Cl3 b. C2H4Cl2 c. C4H8Cl4 d. CH2Cl

B

What is the volume of 0.132 mol of carbon dioxide gas at STP? a. 333 L b. 2.96 L c. 5.81 L d. 170. L

B

What masses of KBr and water are needed to produce 300. g of a solution that is 3.00 % by mass? a. 291 g of KBr and 9.00 g of water b. 9.00 g of KBr and 291 g of water c. 300. g of KBr and 9.00 g of water d. 9.00 g of KBr and 300. g of water

B

Which element is solid at room temperature and a good conductor of heat and electricity? A. Phosphorus B. Calcium C. Hydrogen D. Boron

B

Which of the following 3rd period elements has the smallest atomic radius? a. S b. Cl c. Na d. Al

B

Which of the following is a pure substance? A. soil B. table salt C. sea water D. air

B

A Ca+2 ion has an electron configuration similar to that of a. xenon. b. neon. c. argon. d. krypton.

C

A hot air balloon is filled to a volume of 44.5 L at 758 torr. What will be the volume of the balloon if the pressure decreases to 748 torr under constant temperature? a. 43.9 L b. 49.0 L c. 45.1 L d. 44.5 L

C

An ionic compound is held together by A. attractive forces between ions of like charges. B. repulsive forces between ions of different charges. C. attractive forces between ions of different charges. D. repulsive forces between ions of like charges.

C

An isotope of sodium has a mass number of 23. What is the number of neutrons for this isotope? A. 23 B. 34 C. 12 D. none of these choices

C

Arrhenius defined base as a substance whose aqueous solution contains an excess of a. chloride ion. b. hydrogen ion. c. hydroxide ion. d. sodium ion.

C

How many atoms are indicated in the formula Ca3(PO4)2? A. 8 B. 4 C. 13 D. 3

C

How many joules of energy are released when 45.0 g of water cools from 18.0 oC to 7.0 oC? A. 495 J B. 791 J C. 2070 J D. 2860 J

C

How many unpaired electrons are there in the ground state of an oxygen atom? a. 0 b. 1 c. 2 d. 3

C

How many valence electrons are present in an atom of carbon in the ground state? a. 1 b. 8 c. 4 d. 2

C

15.6 g of a metal absorbs 836.8 J of heat energy that raises its temperature by 21 oC. What is the specific heat of the metal? A. 0.39 J/goC B. 620 J/goC C. 1100 J/goC D 2.6 J/goC

D

A 48.0-g piece of metal is dropped into 50.0 mL of water in a graduated cylinder. The water level rises to 62.4 mL. What is the density of the metal? A. 12.4 g/mL B. 0.258 g/ml C. 595 g/ml D. 3.87 g/mL

D

A sample of gas has a volume of 200. mL at 20.0 ° C. What will be its volume at 40.0 °C, pressure remaining constant? a. 100. mL b. 400. mL c. 18.8 mL d. 214 mL

D

At which pressure would a 2.60 mol sample of gas at 20.0°C have a volume of 25.0 L? a. 15.8 atm b. 0.171 atm c. 2.08 atm d. 2.50 atm

D

Given the unbalanced equation: C6H6 + O2 CO2 + H2O. When properly balanced, the coefficient of oxygen is a. 1. b. 9. c. 12. d. 15.

D

How many moles of hydrogen gas will be produced when 0.500 mol Mg react with hydrochloric acid according to the following reaction? 2Mg + 2HCl 2MgCl2 + H2 a. 1.0 mol b. 0.50 mol c. 1.5 mol d. 0.25 mol

D

In which of the following compounds does hydrogen bonding occur? a. SiH4 b. HI c. LiH d. NH3

D

Ions can be formed from atoms by losing or gaining electrons. Select the alternative that states the correct number of protons, neutrons, and electrons in 𝐀𝐥𝟑+ 𝟏𝟑 𝟐𝟕 . A. 10 protons, 17 neutrons, 13 electrons B. 13 protons, 27 neutrons, 10 electrons C. 13 protons, 14 neutrons, and 16 electrons D. 13 protons, 14 neutrons, and 10 electrons

D

Naturally occurring neon exists as three isotopes. 90.51% is Ne-20 with a mass of 19.99 amu, 0.27% is Ne-21 with a mass of 20.99 amu, and 9.22% is Ne-22 with a mass of 21.99 amu. What is the atomic mass of neon? A. 10.00 amu B. 62.97 amu C. 20.99 amu D. 20.18 amu

D

Perform the following set of operations and choose the alternative that expresses the result to the proper number of significant figures. ((1.5 × 10-4 ) x (61.3)) + 2.01 A. 2.0192 B. 2.0 C. 2.019 D. 2.02

D

The following reaction: 2FeO 2Fe + O2, is an example of a. combination. b. single-displacement. c. double-displacement. d. decomposition.

D

The following reaction: LiOH + HCl LiCl + H2O, is an example of a. single-displacement. b. combination. c. decomposition. d. double-displacement.

D

The normal boiling point of a liquid is the temperature at which its vapor pressure equals a. 100 torr. b. 337 torr. c. 373 torr. d. 760 torr

D

The solubility of ammonium chloride at 70. °C is 60. g of solute per 100. g of water. Which solution would be saturated at 70. °C? a. 90. g of solute in 180. g of water b. 35 g of solute in 50. g of water c. 90 .g of solute in 200. g of water d. 30. g of solute in 50. g of water

D

What is the formula of aluminum sulfide? A. AlSO4 B. AlS C. Al2(SO4)3 D. Al2S3

D

What is the molar mass of sodium chloride? a. 67.53 g b. 6.02 x 1023 g c. 1.00 g d. 58.44 g

D

What is the pH of a 0.034 M hydrochloric acid solution? a. -2.00 b. 3.40 c. -1.47 d. 1.47

D

What is the percent by mass of oxygen in carbon dioxide? a. 27.27% b. 42.86% c. 366.6% d. 72.71%

D

What is the percent yield in a reaction in which 1.038 g of a product is actually produced when the theoretical yield is 1.132 g? a. 8.304% b. 109.1% c. 89.16% d. 91.70%

D

What mass of CO2 is produced when 50.0 g of C2H4 reacts completely in the following equation? (Molar mass: C2H4 28.0 g, CO2 44.0 g) C2H4 + 3O2 2CO2 + 2H2O a. 12.3 g b. 39.2 g c. 49.4 g d. 157 g

D

What quantity of heat is required to change 40.0 g of ice at melting point to liquid water? The heat of fusion of ice is 335 J/g. a. 0.119 J b. 8.38 J c. 375 J d. 13400 J

D

Which of the following bonds is most polar? Electronegativity values: F=4.0, O=3.5,N=3.0, Br=2.8, C=2.5. a. O―F b. N―F c. Br―F d. C―F

D

Which structure represents the best Lewis structure for O2? a. 6-4 b. 5-5 c. 3---3 d. 4--4

D