Final Exam(Chem)

What volume does 7.50 × 1020 molecules of O2 occupy at STP? A) 22.4 L B) 1.68 × 1022 L C) 0.0279 L D) 2.79 L

0.0279 L

.A patient's systolic pressure is measured as 128 mm Hg. What is this pressure in units of atm? A) 128 atm B) 1.28 atm C) 0.168 atm D) 9.73 x 104 atm

0.168 atm

How many moles are contained in 5.33 L of O2 at standard temperature and pressure? A) 5.33 mol of O2 B) 22.4 mol of O2 C) 0.238 mol of O2 D) 1.00 mol of O2

0.238 mol of O2

A sample of neon gas has a volume of 5.0 mL at a pressure of 1.50 atm. What is the pressure exerted by the gas if the volume is increased to 30.0 mL, at constant temperature? A) 0.25 atm B) 9.0 atm C) 1.5 atm D) 0.21 atm

0.25 atm

What is the molarity of a solution made by dissolving 36.29g of NaCl in 2.30 L of solution? A) 15.78 M NaCl B) 0.0634 M NaCl C) 0.270 M NaCl D) 2.70 M NaCl

0.270 M NaCl

What is the concentration of a solution formed by diluting 25.0 mL of a 3.2 M NaCl solution to 135.0 mL? A) 17 M NaCl B) 0.59 M NaCl C) 0.50 M NaCl D) 2.7 M NaCl

0.59 M NaCl

Which solution has the highest pH? A) 4.3 × 10-8 M H3O+ B) 1.0 × 10-7 M H3O+ C) 1.0 × 10-2 M H3O+ D) 1.9 × 10-8 M H3O+ E) 5.1 × 10-2 M H3O+

1.9 × 10-8 M H3O+

Carry out the following calculation and report the answer using the proper number of significant figures: 38.251 + 73.1 A) 111 B) 111.3 C) 111.4 D) 111.35 E) 111.351

111.4

Atmospheric pressure in interstellar space is approximately 1 × 10-17 torr at a temperature of -173 °C. How many gas molecules are present in 25,000 L of interstellar space (about the volume of a bedroom)? A) 2 × 107 molecules B) 2 × 1010 molecules C) 4 × 10-17 molecules D) 3 × 10-14 molecules

2 × 107 molecules

Which volume is equivalent to 225 mL? A) 2.25 × 105 µL B) 2.25 × 10-5 µL C) 2.25 × 102µL D) 0.225 µL E) 2.25 L

2.25 × 105 µL

How many covalent bonds are generally formed by atoms with five valence electrons? 8-5=3 (8 total in th valence electrons) A) 1 B) 2 C) 3 D) 4 E) 5

3

How much energy in calories is absorbed when 50.0 g of ice cubes melt? The heat of fusion of water is 79.7 cal/g. A) 3,900 cal B) 4,000 cal C) 3,980 cal D) 3,990 cal

3,990 cal

What is the pH of a peach with a [-OH] = 3.2 × 10-11 M -OH? A) 11.32 B) 10.49 C) 3.51 D) 3.2

3.51

The temperature of a 0.750-L gas sample at 25 °C and 2.00 atm is changed to 250 °C. What is the final pressure of the system, at constant volume? A) 20.0 atm B) 0.200 atm C) 3.51 atm D) 0.427 atm

3.51 atm

Which gas sample contains the largest number of moles? A) 4.0 L of O2 at 273 K and 530 mm Hg B) 4.5 L of N2 at 298 K and 610 mm Hg C) 3.8 L of He at 250 K and 880 mm Hg D) 5.0 L Ar at 300 K and 710 mm Hg

3.8 L of He at 250 K and 880 mm Hg

Carry out the following calculation and report the answer using the proper number of significant figures: 16.75 ft/0.54s A) 31.0185 ft/s B) 31.01 ft/s C) 31.02 ft/s D) 31.0 ft/s E) 31 ft/s

31 ft/s

If 400. Cal of heat is added to 25.0 g of 2-propanol at 21°C, what is the final temperature? A) 26°C B) 47°C C) 52°C D) 5°C

47°C

What is the volume of 62.3 g of nitrogen gas at STP? A) 22.4 L B) 49.8 L C) 99.6 L D) 2.78 L

49.8 L

An alpha particle is a high-energy particle that contains A) One proton and one neutron. B) One electron. C) Two protons and two neutrons. D) One proton.

Two protons and two neutrons.

In the chemical equation 2 Co(NO3)3 + 3 (NH4)2S → Co2S3 + 6 NH4NO3 , how many nitrogen atoms are on each side of the equation? A) 2 B) 3 C) 6 D) 12 E) 16

12

Predict the bond angles around the carbon atom in the structure of carbonic acid shown below. Don't forget to draw in lone pairs where needed to give octets. H-O-C=O-O-H A) 180° B) 120° C) 109.5° D) 90°

120°

A patient's urine sample has a density of 1.02 g/mL. If the patient excreted 1250 mL of urine in one day, what mass of urine was eliminated? A) 1.28 kg B) 1225 g C) 1275 g D) 128 g

1275 g

What is the mass of 3.81 mol of PH3? A) 34.0 g B) 3.81 g C) 8.92 g D) 130. g

130. g

What is the atomic number of the isotope with the symbol 3717Cl ? A) 17 B) 18 C) 35.45 D) 37

17

What is the maximum number of electrons that can occupy the third (n=3) shell? A) 2 B) 3 C) 6 D) 8 E) 18

18

What is the electron configuration of an F- ion? A) 1s22s22p4 B) 1s22s22p5 C) 1s22s22p6 D) 1s22s22p63s1

1s22s22p6

Which chemical equation is properly balanced? A) SO2 + O2 + H2O → H2SO4 B) 2 SO2 + O2 + 2 H2O → 2 H2SO4 C) 4 SO2 + O2 + 4 H2O → 4 H2SO4 D) SO2 + O2 + 4 H2O → 2 H2SO4

2 SO2 + O2 + 2 H2O → 2 H2SO4

What is the chemical formula for the ionic compound calcium selenide? A) Ca2Se2 B) CaSe C) CaSe2 D) Ca2Se

CaSe

5. Consider the oxidation of sodium metal to sodium oxide described by the balanced equation: 4 Na + O2 → 2 Na2O. What is the theoretical yield of Na2O in grams from 9.0 mol of O2? A) 11 g of Na2O B) 410 g of Na2O C) 1,100 g of Na2O D) 280 g of Na2O E) 560 g of Na2O

1,100 g of Na2O

The pH of a lime is 1.90. What is the [H3O+]? A) 1.3 × 10-2 M H3O+ B) 7.9 × 10-13 M H3O+ C) 1.3 × 1012 M H3O+ D) 1.9 M H3O+ E) 7.9 × 101 M H3O+

1.3 × 10-2 M H3O+

The [H3O+] in a cabernet sauvignon wine is 5.9 × 10-4 M. What is the [-OH] in this wine? A) 5.9 × 10-4 M -OH B) 1.7 × 10-11 M -OH C) 1.0 × 10-7 M -OH D) 1.0 × 10-14 M -OH E) 5.9 × 10-18 M -OH

1.7 × 10-11 M -OH

Which species completes the nuclear equation shown below? 218 84Po → _____ + 4 2He A) 214 82Po B) 214 82Pb C) 222 86Rn D) 222 86Po

214 82Pb

What is the estimated age of an artifact that has 1/16 of the amount of carbon-14 (relative to carbon-12) compared to living organisms? (C-14 t1/2 = 5,730 years) A) 358 years B) 22,920 years C) 5,730 years D) 28,650 years E) 17,190 years

22,920 years

How many protons and electrons are present in Co2+? A) 27 protons, 27 electrons B) 27 protons, 29 electrons C) 27 protons, 25 electrons D) 29 protons, 27 electrons

27 protons, 25 electrons

How many grams of oxygen gas are required to completely react with 77.28 g of ethane (C2H6) in the balanced redox reaction: 2 C2H6(g) + 7 O2(g) → 4 CO2(g) + 6 H2O(g)? A) 77.28 g of O2(g) B) 8.995 g of O2(g) C) 23.50 g of O2(g) D) 143.9 g of O2(g) E) 287.8 g of O2(g)

287.8 g of O2(g)

A solution is made by mixing 569 mL of water and 238 mL ethanol. What is the concentration of ethanol in units of volume/volume percent? A) 41.8% (v/v) ethanol B) 0.418% (v/v) ethanol C) 29.5% (v/v) ethanol D) 0.295% (v/v) ethanol E) 70.5% (v/v) ethanol

29.5% (v/v) ethanol

. Hydrogen peroxide decomposes to give water and oxygen gas according to the equation below. If 3.0 moles of hydrogen peroxide decompose, what volume of oxygen gas is produced at a pressure of 1.0 atm and a temperature of 23 °C? 2 H2O2(l) → 2 H2O(l) + O2(g) A) 1.9 L of O2 B) 2.8 L of O2 C) 24 L of O2 D) 36 L of O2

36 L of O2

What is the mass number of the isotope with the symbol 3717Cl ? A) 17 B) 18 C) 35.45 D) 37

37

. Potassium metal (K) reacts violently when added to water according to the balanced equation: 2 K(s) + 2 H2O(l) → 2 KOH(aq) + H2(g). How many moles of H2O are needed to react completely with 7.54 mol of K? A) 2 mol of H2O B) 7.54 mol of H2O C) 15.1 mol of H2O D) 3.77 mol of H2O

7.54 mol of H2O

The measurement 78,005,760 expressed correctly using scientific notation is A) 7.8005760 × 107 B) 7.800576 × 10-7 C) 7.8005760 × 10-7 D) 7.800576 × 107 E) 7.8 × 107

7.800576 × 10(7)

A gas cylinder containing 6.38 mol of neon has a pressure of 491 mm Hg at 295 K. If 3.22 mol of helium is added to this cylinder, at constant temperature and volume, what will be the pressure in the cylinder? A) 9.73 mm Hg B) 739 mm Hg C) 1460 mm Hg D) 248 mm Hg

739 mm Hg

A sample of gas contains four gases with the following partial pressures: He (113 mm Hg), Ne (184 mm Hg), Ar (35 mm Hg), and Xe (445 mm Hg). What is the total pressure of the sample? A) 777 mm Hg B) 760. mm Hg C) 445 mm Hg D) 332 mm Hg

777 mm Hg

Blimps are essentially very large helium filled balloons. If a blimp contains 536 kg of helium, how many helium atoms are present inside the blimp? A) 134,000 He atoms B) 8.06 x 1028 He atoms C) 8.9 x 10-19 He atoms D) 3.23 x 1026 He atoms

8.06 x 1028 He atoms

How many moles of chloroethylene (C2H3Cl) contain 5.47 × 1026 molecules? A) 3.29 × 1050 mol of C2H3Cl B) 5.47 × 1026 mol of C2H3Cl C) 909 mol of C2H3Cl D) 5450 mol of C2H3Cl

909 mol of C2H3Cl

Which is not an example of a pure substance? A) Sugar B) Air C) Aluminum foil D) Water E) A block of dry ice

Air

What is the formula for the ionic compound formed when aluminum and sulfur combine? A) AlS B) Al2S3 C) AlS3 D) Al2S

Al2S3

The electron configuration of chlorine is 1s22s22p63s23p5. Which statement about chlorine is incorrect? A) Chlorine has five valence electrons B) Chlorine's valence shell is the third shell C) Chlorine has five electrons in the 3p subshell D) Chlorine has 17 total electrons

Chlorine has five valence electrons

Which element has the smallest ionization energy? A) K B) Ga C) Br D) Rb

Rb

Which atom has the smallest atomic radius? A) K B) Ga C) Br D) Rb

Br

What period 4 element forms an ion with a -1 charge? A) Sulfur B) Bromine C) Iodine D) Rubidium

Bromine

Which term correctly describes a reaction in which the energy of the products is higher than the energy of the reactants? A) Oxidation-reduction B) Endothermic C) Exothermic D) Combustion

Endothermic

Which of the following is true about melting? A) Energy is released in melting B) Energy is absorbed in melting C) Melting is the opposite of vaporization D) Melting is the opposite of sublimation

Energy is absorbed in melting

Which species is the conjugate acid of HCO3-? A) CO32- B) H2CO3 C) CO2 D) H2O

H2CO3

In the acid-base reaction: F-(aq) + HNO3(aq) HF(aq) + NO3-(aq) A) F- is the acid and its conjugate base is HF, and HNO3 is the base and its conjugate acid is NO3-(aq). B) HNO3 is the acid and its conjugate base is NO3-(aq), and F- is the base and its conjugate acid is HF. C) F- is the acid and its conjugate base is NO3-(aq), and HNO3 is the base and its conjugate acid is HF. D) HNO3 is the acid and its conjugate base is HF, and F- is the base and its conjugate acid is NO3-(aq).

HNO3 is the acid and its conjugate base is NO3-(aq), and F- is the base and its conjugate acid is HF.

Which element is not an alkali metal? A) Li B) K C) Rb D) H E) All of the above elements are alkali metals.

HYDROGEN

Propanol, CH3CH2CH2OH, has the structure shown below. What is the strongest type of intermolecular force that exists between two propanol molecules? CH3,CH2,CH2,OH A) London dispersion forces B) Hydrogen bonding C) Temporary dipole interactions D) Dipole-dipole interactions

Hydrogen bonding

Rank the atoms Br, Cl, and K in order of increasing electronegativity. A) K < Br < Cl B) Cl < Br < K C) Br < Cl < K D) K < Cl < Br

K < Br < Cl

Which element is a noble gas? A) H B) Ne C) Pr D) Ra E) More than one of the elements listed is a noble gas.

Ne

What is the expression for Kw, the ion-product constant for water? A) Kw = [H2O]2 B) Kw =+322[H O ][ OH][H O]− C) Kw = +3 [H O ][ OH] − D) Kw =+3 [H O ][ OH]

Kw = +3 [H O ][ OH] −

When octane evaporates, what kind of attractive forces are overcome? CH3-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3 octane A) Covalent bonding between carbon and hydrogen atoms B) Hydrogen bonding between octane molecules C) Dipole-dipole interactions between octane molecules D) London dispersion forces between octane molecules

London dispersion forces between octane molecules

What is the proper name for MgF2? A) Magnesium fluoride B) Magnesium (I) fluoride C) Magnesium (II) fluoride D) Magnesium difluoride

Magnesium fluoride

Which is an example of a physical change? A) The rusting of an iron nail B) The burning of propane in a gas grill C) Baking cookies D) Polishing tarnished silver E) Melting of an ice cube in a glass of soda

Melting of an ice cube in a glass of soda

What is the formula for the ionic compound formed when magnesium and oxygen combine? A) MgO B) MgO2 C) Mg2O D) Mg2O2

MgO

Nonpolar compounds are soluble in A) Ionic compounds. B) Electrolytes. C) Polar solvents. D) Nonpolar solvents.

Nonpolar solvents.

Which element may have more than eight valence electrons around it when present in a covalent compound? A) C B) B C) N D) P E) O

P

Which type of radiation has a negligible mass and a charge of +1? A) Alpha particle B) Gamma ray C) Positron D) Beta particle

Positron

Which element is chemically similar to lithium? A) Sulfur B) Magnesium C) Iron D) Lanthanum E) Potassium

Potassium

Which element is a transition metal in period 4? A) K B) Hf C) Sn D) Sc

Sc

Silicon has three naturally occurring isotopes: Si-28, Si-29 and Si-30. If the average atomic mass of silicon is 28.09, which isotope has the highest isotopic abundance? A) Si-28 B) Si-29 C) Si-30 D) All isotopes have the same isotopic abundance.

Si-28

What is the chemical formula of tin (IV) cyanide? A) Sn4CN B) SnCN4 C) Sn(CN)4 D) SnC4N4

Sn(CN)4

The density of human urine is normally between 1.003 and 1.030g/mL, and is often used as a diagnostic tool. If a 25.00 mL sample of urine from a patient has a mass of 26.875 g, how does the density of the urine sample compare to the normal range? A) The density of the sample is lower than the normal range B) The density of the sample is greater than the normal range C) The density of the sample is within the normal range D) There is insufficient information to make a comparison

The density of the sample is greater than the normal range

Consider the following graph. What is happening to the substance along the diagonal C → D? A) The substance is melting. B) The substance is boiling. C) The substance is condensing. D) The substance is a liquid and is being heated. E) The substance is a gas and is being heated.

The substance is a liquid and is being heated.

What is the molecular shape around the phosphorus atom in PH3? A) Linear B) Bent C) Trigonal planar D) Tetrahedral E) Trigonal pyramidal

Trigonal pyramidal