Deck 3: Mass Relations in Chemistry;stoichiometry

Question 1

Which is a correct method for determining the mass in grams of 0.190 mol silver?

A) $0.190 \mathrm{~mol} \mathrm{Ag}\left(\frac{107.9 \mathrm{~g}}{\mathrm{~mol}}\right)$
B) $0.190 \mathrm{~mol} \mathrm{Ag}\left(\frac{1 \mathrm{~g}}{107.9 \mathrm{~mole}}\right)$
C) $\left(\frac{1}{0.190 \mathrm{~mol} \mathrm{Ag}}\right)\left(\frac{107.9 \mathrm{~g}}{\mathrm{~mol}}\right)$
D) $107.9 \mathrm{~mol} \mathrm{~Ag}\left(\frac{1 \mathrm{~g}}{0.190 \mathrm{~mol}}\right)$
E) none of the above

Answer 1

$0.190 \mathrm{~mol} \mathrm{Ag}\left(\frac{107.9 \mathrm{~g}}{\mathrm{~mol}}\right)$

Question 2

Which of the following samples contains the largest number of hydrogen atoms?

A) 2.0 moles of C₆H₁₆
B) 3.0 moles of C₃H₈
C) 4.0 moles of C₃H₆
D) 6.0 moles of C₂H₄
E) 8.0 moles of C₂H₂

Answer 2

2.0 moles of C₆H₁₆

Question 3

What is the mass in grams of 0.362 moles barium chloride (BaCl₂)?

A) 0.362 g
B) 0.00174 g
C) 75.4 g
D) 208 g
E) 575 g

Answer 3

75.4 g

Question 4

Which is a correct method for determining the total number of atoms in 123 grams of sulfur trioxide (SO₃)?

A) $123 \mathrm{~g} \mathrm{~SO}_{3}\left(\frac{1 \mathrm{~mol}}{80.07 \mathrm{~g}}\right)\left(\frac{1 \text { atom }}{6.022 \times 10^{23} \mathrm{~mol}}\right)$
B) $123 \mathrm{~g} \mathrm{~SO}_{3}\left(\frac{1 \mathrm{~mol}}{80.07 \mathrm{~g}}\right)\left(\frac{6.022 \times 10^{23} \text { atoms }}{1 \mathrm{~mol}}\right)$
C) $123 \mathrm{~g} \mathrm{~SO}_{3}\left(\frac{1 \mathrm{~mol}}{80.07 \mathrm{~g}}\right)\left(\frac{1 \mathrm{~mol} \mathrm{atoms}}{4 \mathrm{~mol} \mathrm{~SO}_{3}}\right)\left(\frac{6.022 \times 10^{23} \text { atoms }}{1 \mathrm{~mol}}\right)$
D) $123 \mathrm{~g} \mathrm{~SO}_{3}\left(\frac{1 \mathrm{~mol}}{80.07 \mathrm{~g}}\right)\left(\frac{4 \mathrm{~mol} \text { atoms }}{1 \mathrm{~mol} \mathrm{SO}_{3}}\right)\left(\frac{1 \text { atom }}{6.022 \times 10^{23} \mathrm{~mol}}\right)$
E) $123 \mathrm{~g} \mathrm{~SO}_{3}\left(\frac{1 \mathrm{~mol}}{80.07 \mathrm{~g}}\right)\left(\frac{4 \mathrm{~mol} \mathrm{atoms}}{1 \mathrm{~mol} \mathrm{SO}_{3}}\right)\left(\frac{6.022 \times 10^{23} \text { atoms }}{1 \mathrm{~mol}}\right)$

Question 5

How many hydrogen atoms are present in 1.0 g of NH₃?

A) 0.059 atoms
B) 0.18 atoms
C) 3.5 × 10²² atoms
D) 1.1 × 10²³ atoms
E) 1.2 × 10²² atoms

Question 6

The molarity of a solution is defined as

A) the moles of solute per liter of solution.
B) the moles of solute per kilogram of solution.
C) the moles of solute per kilogram of solvent.
D) the mass of solute (in grams)per liter of solution.
E) the mass of solute (in grams)per liter of solvent.

Question 7

You have a 5.0 g sample of each of the following elements: Ra,Rb,Rh,Rn,Ru.Which sample contains the most atoms?

A) Ra
B) Rb
C) Rh
D) Rn
E) Ru

Question 8

The molar mass of nitrogen (N₂)is 28.0 g/mole.What is the mass of a single nitrogen atom?

A) 2.32 × 10−²³ g
B) 4.65 × 10−²³ g
C) 9.30 × 10−²³ g
D) 4.30 × 10−²² g
E) 8.43 × 10−²² g

Question 9

What mass of chlorine is present in 5.00 grams of carbon tetrachloride (CCl₄)?

A) 0.130 g
B) 1.15 g
C) 0.564 g
D) 4.61 g
E) 0.922 g

Question 10

The molar mass of platinum is 195.08 g/mol.What is the mass of 1.00 × 10² Pt atoms?

A) 8.51 × 10^-25 g
B) 3.24 × 10^-24 g
C) 1.67 × 10^-22 g
D) 3.24 × 10^-22 g
E) 3.24 × 10^-20 g

Question 11

The molar mass of boron is 10.81 g/mole.What is the mass of a single boron atom?

A) 1.661 × 10−²⁴ g
B) 1.795 × 10−²³ g
C) 6.510 × 1024 g
D) 1.536 × 10−²⁵ g
E) 1.081 × 101 g

Question 12

How many moles of HCl are present in 0.098 grams of HCl?

A) 0.00083 mol
B) 0.0027 mol
C) 0.28 mol
D) 3.6 mol
E) 380 mol

Question 13

Which is a correct method for calculating the moles of calcium carbonate present in 132 grams of calcium carbonate?

A) $132 \mathrm{~g} \mathrm{CaCO}_{3}\left(\frac{6.022 \times 10^{23} \text { atoms }}{1 \mathrm{~mol}}\right)\left(\frac{100.1 \mathrm{~mol}}{1 \mathrm{~g}}\right)$
B) $132 \mathrm{~g} \mathrm{CaCO}_{3}\left(\frac{1 \mathrm{~mol}}{100.1 \mathrm{~g}}\right)$
C) $132 \mathrm{~g} \mathrm{CaCO}_{3}\left(\frac{100.1 \mathrm{~g}}{1 \mathrm{~mol}}\right)$
D) $132 \mathrm{~g} \mathrm{CaCO}_{3}\left(\frac{100.1 \mathrm{~mol}}{1 \mathrm{~g}}\right)$
E) none of the above

Question 14

What is the mass in grams of 0.338 mol of glucose (C₆H₁₂O₆)?

A) 0.00188 g
B) 0.0164 g
C) 1.88 g
D) 53.3 g
E) 60.9 g

Question 15

A 1.45 g sample of chromium contains ____ atoms.

A) 1.25 × 10²²
B) 1.68 × 10²²
C) 8.73 × 10²³
D) 2.16 × 10²⁵
E) 4.54 × 10²⁵

Question 16

What is the mass of 0.71 mol Na?

A) 1.2 × 10^-24 g
B) 12 g
C) 16 g
D) 0.031 g
E) 32 g

Question 17

Which of the following samples contains the largest number of atoms?

A) 2.0 moles of H₃PO₄
B) 3.0 moles of H₂SO₃
C) 4.0 moles of HNO₃
D) 6.0 moles of HClO
E) 8.0 moles of HBr

Question 18

What mass of oxygen is present in 10.0 grams of potassium nitrate (KNO₃)?

A) 4.75 g
B) 5.43 g
C) 6.39 g
D) 8.00 g
E) 9.17 g

Question 19

How many atoms are present in 5.00 grams of iron?

A) 8.95 × 10−²³ atoms
B) 3.36 × 10¹⁸ atoms
C) 1.88 × 10²¹ atoms
D) 5.39 × 10²² atoms
E) 3.36 × 10²⁶ atoms

Question 20

The mass of a single atom of chlorine atom is 5.887 × 10?²³ grams.Which is a correct method for determining the molar mass of elemental chlorine,Cl₂?

A) $\frac{5.887 \times 10^{-23} \mathrm{~g}}{1 \text { atom Cl }}\left(\frac{1 \text { atom }}{6.022 \times 10^{23} \text { mole }}\right)\left(\frac{1 \mathrm{~mole} \mathrm{~Cl}_{2}}{2 \mathrm{~mole} \mathrm{~Cl}}\right)$
B) $\frac{5.887 \times 10^{-23} \mathrm{~g}}{1 \text { atom } \mathrm{Cl}}\left(\frac{6.022 \times 10^{23} \text { atoms }}{1 \mathrm{~mole}}\right)\left(\frac{2 \mathrm{~mole} \mathrm{Cl}}{1 \mathrm{~mole} \mathrm{Cl}_{2}}\right)$
C) $\frac{5.887 \times 10^{-23} \mathrm{~g}}{1 \text { atom Cl }}\left(\frac{1 \text { atom }}{6.022 \times 10^{23} \mathrm{~mole}}\right)\left(\frac{2 \mathrm{~mole} \mathrm{Cl}}{1 \mathrm{~mole} \mathrm{Cl}_{2}}\right)$
D) $\frac{1 \text { atom Cl }}{5.887 \times 10^{-23} \mathrm{~g}}\left(\frac{6.022 \times 10^{23} \mathrm{~mole}}{1 \text { atom }}\right)\left(\frac{1 \mathrm{~mole} \mathrm{Cl}_{2}}{2 \mathrm{~mole} \mathrm{Cl}}\right)$
E) $\frac{5.887 \times 10^{-23} \mathrm{~g}}{1 \text { atom } \mathrm{Cl}}\left(\frac{6.022 \times 10^{23} \text { atoms }}{1 \mathrm{~mole}}\right)\left(\frac{1 \mathrm{~mole} \mathrm{Cl}_{2}}{2 \mathrm{~mole} \mathrm{Cl}}\right)$

Question 21

An oxide of nitrogen contains 63.1% oxygen and has a molar mass of 76.0 g/mol.What is the molecular formula for this compound?

A) N₂O
B) NO
C) NO₂
D) N₂O₃
E) N₂O₅

Question 22

Combustion analysis of 0.800 grams of an unknown hydrocarbon yields 2.613 g CO₂ and 0.778 g H₂O.What is the percent composition of the hydrocarbon?

A) 66.6% C;33.4% H
B) 82.3% C;17.7% H
C) 89.1% C;10.9% H
D) 92.4% C;7.60% H
E) not enough information given to solve the problem

Question 23

What is the mass percent of each element in sulfuric acid,H₂SO₄?

A) 2.055% H,32.69% S,65.25% O
B) 1.028% H,32.69% S,66.28% O
C) 28.57% H,14.29% S,57.17% O
D) 1.028% H,33.72% S,65.25% O
E) 2.016% H,32.07% S,65.91% O

Question 24

A mass of 12.0 g of calcium chloride is diluted to a volume of 250 mL in a volumetric flask.Which of the equations below is a correct method for determining the chloride ion concentration?

A) $\frac{12.0 \mathrm{~g} \mathrm{~CaCl}_{2}}{250 \mathrm{~mL}}\left(\frac{1000 \mathrm{~mL}}{1 \mathrm{~L}}\right)\left(\frac{1 \mathrm{~mole} \mathrm{CaCl}_{2}}{111.0 \mathrm{~g}}\right)$
B) $\frac{12.0 \mathrm{~g} \mathrm{~CaCl}_{2}}{250 \mathrm{~mL}}\left(\frac{1 \mathrm{~L}}{1000 \mathrm{~mL}}\right)\left(\frac{1 \mathrm{~mole} \mathrm{CaCl}_{2}}{111.0 \mathrm{~g}}\right)\left(\frac{2 \mathrm{~mol} \mathrm{Cl}^{-}}{1 \mathrm{~mol} \mathrm{CaCl}_{2}}\right)$
C) $\frac{12.0 \mathrm{~g} \mathrm{~CaCl}_{2}}{250 \mathrm{~mL}}\left(\frac{1000 \mathrm{~mL}}{1 \mathrm{~L}}\right)\left(\frac{1 \mathrm{~mole} \mathrm{CaCl}_{2}}{111.0 \mathrm{~g}}\right)\left(\frac{2 \mathrm{~mol} \mathrm{Cl}^{-}}{1 \mathrm{~mol} \mathrm{CaCl}_{2}}\right)$
D) $\frac{12.0 \mathrm{~g} \mathrm{~CaCl}_{2}}{250 \mathrm{~mL}}\left(\frac{1 \mathrm{~L}}{1000 \mathrm{~mL}}\right)\left(\frac{1 \mathrm{~mole} \mathrm{CaCl}_{2}}{111.0 \mathrm{~g}}\right)\left(\frac{1 \mathrm{~mol} \mathrm{CaCl}_{2}}{2 \mathrm{~mol} \mathrm{Cl}^{-}}\right)$
E) $\frac{12.0 \mathrm{~g} \mathrm{~CaCl}_{2}}{250 \mathrm{~mL}}\left(\frac{1000 \mathrm{~mL}}{1 \mathrm{~L}}\right)\left(\frac{1 \mathrm{~mole} \mathrm{CaCl}_{2}}{111.0 \mathrm{~g}}\right)\left(\frac{1 \mathrm{~mol} \mathrm{CaCl}_{2}}{2 \mathrm{~mol} \mathrm{Cl}^{-}}\right)$

Question 25

If 5.15 g Fe(NO₃)₃ is dissolved in enough water to make exactly 150.0 mL of solution,what is the molar concentration of nitrate ion?

A) 0.00319 M
B) 0.0343 M
C) 0.142 M
D) 0.313 M
E) 0.426 M

Question 26

What is the mass of sodium iodide in 50.0 mL of 2.63 × 10^-2 M NaI(aq)?

A) 0.00132 g
B) 0.00877 g
C) 0.0788 g
D) 0.197 g
E) 78.8 g

Question 27

Hydrazine,a fuel used to power rocket engines,is a product of the reaction between ammonia and bleach.Balance the equation for the reaction. aNH₃(aq)+ bOCl−(aq)→ cN₂H₄(l)+ dCl−(aq)+ eH₂O(l)

A) a = 2,b = 1,c = 1,d = 1,e = 1
B) a = 2,b = 2,c = 1,d = 2,e = 2
C) a = 2,b = 1,c = 2,d = 1,e = 2
D) a = 4,b = 3,c = 1,d = 3,e = 1
E) a = 4,b = 3,c = 2,d = 3,e = 2

Question 28

Isopentyl acetate,a molecule composed of C,H,and O,smells like bananas.Combustion analysis of 1.750 grams of this molecule yields 1.695 g H₂O and 4.142 g CO₂.What is the simplest formula for isopentyl acetate?

A) C₇H₁₄O₂
B) C₇H₇O₄
C) C₈H₁₀O₃
D) C₈H₁₆O
E) C₉H₆O

Question 29

Nitrogen and oxygen form an extensive series of oxides with the general formula N_xO_y.What is the empirical formula for an oxide that contains 30.44% by mass nitrogen?

A) N₂O
B) NO
C) NO₂
D) N₂O₃
E) N₂O₅

Question 30

What volume of 0.15 M HCl(aq)must be diluted to make 2.0 L of 0.050 M HCl(aq)?

A) 0.015 L
B) 0.10 L
C) 0.30 L
D) 0.67 L
E) 6.0 L

Question 31

What is the percent composition of iron(II)sulfate hexahydrate?

A) 4.2% Fe;4.2% S;41.6% O;50.0% H
B) 16.7% Fe;16.7%S;66.6% O
C) 21.5% Fe;12.3%S;24.6% O;41.6% H
D) 21.5% Fe;12.3%S;61.5% O;4.7% H
E) 36.8% Fe;21.1%S;42.1% O

Question 32

What is the maximum volume of 0.25 M KCl(aq)that can be prepared from 75 g KCl(s)?

A) 0.33 L
B) 1.0 L
C) 3.0 L
D) 4.0 L
E) 19 L

Question 33

If 8.19 g KIO₃ is dissolved in enough water to make 500.0 mL of solution,what is the molarity of the potassium iodate solution? The molar mass of KIO₃ is 214 g/mol.

A) 1.64 × 10^-2 M
B) 1.91 × 10^-2 M
C) 7.65 × 10^-2 M
D) 3.51 M
E) 16.4 M

Question 34

Which is a correct method for determining the mass of carbon present in 0.132 grams of propane (C₃H₈)?

A) $0.132 \mathrm{~g} \mathrm{C}_{3} \mathrm{H}_{8}\left(\frac{1 \mathrm{~mol} \mathrm{C}_{3} \mathrm{H}_{8}}{44.09 \mathrm{~g}}\right)\left(\frac{12.01 \mathrm{~g} \mathrm{C}}{1 \mathrm{~mole}}\right)$
B) $0.132 \mathrm{~g} \mathrm{C}_{3} \mathrm{H}_{8}\left(\frac{1 \mathrm{~mol} \mathrm{C}_{3} \mathrm{H}_{8}}{44.09 \mathrm{~g}}\right)$$\left(\frac{3 \mathrm{gC}}{1 \mathrm{~mol} \mathrm{C}_{3} \mathrm{H}_{8}}\right)$
C) $0.132 \mathrm{~g} \mathrm{C}_{3} \mathrm{H}_{8}\left(\frac{44.09 \mathrm{~mol} \mathrm{C}_{3} \mathrm{H}_{8}}{1 \mathrm{~g}}\right)$$\left(\frac{3 \mathrm{~mol} \mathrm{C}}{1 \mathrm{~mol} \mathrm{C}_{3} \mathrm{H}_{8}}\right)\left(\frac{12.01 \mathrm{gC}}{1 \mathrm{~mole}}\right)$
D) $0.132 \mathrm{~g} \mathrm{C}_{3} \mathrm{H}_{8}\left(\frac{1 \mathrm{~mol} \mathrm{C}_{3} \mathrm{H}_{8}}{44.09 \mathrm{~g}}\right)$$\left(\frac{1 \mathrm{~mol} \mathrm{C}}{3 \mathrm{~mol} \mathrm{C}_{3} \mathrm{H}_{8}}\right)\left(\frac{12.01 \mathrm{~g} \mathrm{C}}{1 \mathrm{~mole}}\right)$
E) $0.132 \mathrm{~g} \mathrm{C}_{3} \mathrm{H}_{8}\left(\frac{1 \mathrm{~mol} \mathrm{C}_{3} \mathrm{H}_{8}}{44.09 \mathrm{~g}}\right)$ $\left(\frac{3 \mathrm{~mol} \mathrm{C}}{1 \mathrm{~mol} \mathrm{C}_{3} \mathrm{H}_{8}}\right)\left(\frac{12.01 \mathrm{gC}}{1 \mathrm{~mole}}\right)$

Question 35

Soft drink bottles are made of polyethylene terephthalate (PET),a polymer composed of carbon,hydrogen,and oxygen.If 2.8880 g PET is burned in oxygen it produces 1.0000 g H₂O and 6.1058 g CO₂.What is the empirical formula of PET?

A) CHO
B) CH₇O₅
C) C₅H₇O
D) C₈H₁₀O
E) C₁₀H₈O₅

Question 36

A molecule is found to contain 47.35% by mass C,10.60% by mass H,and 42.05% by mass O.What is the empirical formula for this molecule?

A) C₂H₆O
B) C₃H₄O
C) C₃H₈O₂
D) C₄H₆O₂
E) C₄H₈O₃

Question 37

How many liters of 0.2805 M C₆H₁₂O₆(aq)contain 1.000 g of C₆H₁₂O₆?

A) 0.001557 L
B) 0.01979 L
C) 0.2805 L
D) 3.565 L
E) 50.5 L

Question 38

Beryl is a mineral which contains 5.03% Be,10.04% Al,31.35% Si,and 53.58% O.What is the simplest formula for beryl?

A) BeAl(SiO₃)₂
B) BeAl(SiO₃)₃
C) Be₃(AlSiO₃)₂
D) Be₃Al₂(SiO₃)₆
E) Be₄Al(SiO₃)₈

Question 39

Polyethylene is a polymer consisting of only carbon and hydrogen.If 2.300 g of the polymer is burned in oxygen it produces 2.955 g H₂O and 7.217 g CO₂.What is the empirical formula of polyethylene?

A) CH
B) CH₂
C) C₂H₃
D) C₅H₈
E) C₇H₈

Question 40

If 25.00 mL of 4.50 M NaOH(aq)is diluted with water to a volume of 750.0 mL,what is the molarity of the diluted NaOH(aq)?

A) 0.0333 M
B) 0.150 M
C) 0.155 M
D) 6.67 M
E) 1.35 × 10³ M

Question 41

If 16.4 g of oxygen gas react with excess hydrogen,what mass of water is produced? 2H₂(g)+ O₂(g)→ 2H₂O(g)

A) 9.23 g
B) 18.5 g
C) 20.4 g
D) 23.9 g
E) 36.9 g

Question 42

What hydrate is sometimes referred to as "the ice that burns"?

A) copper(II)sulfate pentahydrate
B) carbon dioxide hydrate
C) methane hydrate
D) cobalt(II)chloride pentahydrate
E) none of the above

Question 43

Iron reacts with hydrochloric acid to produce iron(II)chloride and hydrogen gas. Fe(s)+ 2 HCl(aq)→ FeCl₂(aq)+ H₂(g)
What mass of H₂(g)is produced from the reaction of 5.2 g Fe(s)with excess hydrochloric acid?

A) 0.094 g
B) 0.19 g
C) 5.2 g
D) 6.8 g
E) 1.4 × 10² g

Question 44

A mass of 8.15 g C₂H₄(g)reacts with excess oxygen.If 16.2 g CO₂(g)is collected,what is the percent yield of the reaction? C₂H₄(g)+ 3O₂(g)→ 2CO₂(g)+ 2H₂O(g)

A) 25.6%
B) 31.7%
C) 41.0%
D) 57.1%
E) 63.3%

Question 45

Under certain conditions the reaction of ammonia with excess oxygen will produce a 24.8% yield of NO.What mass of NH₃ must react with excess oxygen to yield 12.5 g NO? 4NH₃(g)+ 5O₂(g)→ 4NO(g)+ 6H₂O(g)

A) 1.76 g
B) 7.10 g
C) 28.6 g
D) 50.4 g
E) 88.8 g

Question 46

The compound P₄S₃ is used in matches.It reacts with oxygen to produce P₄O₁₀ and SO₂.The unbalanced chemical equation is shown below. P₄S₃(s)+ O₂(g)→ P₄O₁₀(s)+ SO₂(g)
What mass of SO₂ is produced from the combustion of 0.331 g P₄S₃?

A) 0.00150 g
B) 0.00451 g
C) 0.0321g
D) 0.0964 g
E) 0.289 g

Question 47

What mass of carbon dioxide can be made by reacting 1.56 grams of sodium bicarbonate with 0.687 grams of hydrochloric acid? NaHCO₃(s)+ H⁺(aq)→ CO₂(g)+ H₂O(l)+ Na⁺(aq)

A) 2.25 g
B) 2.98 g
C) 0.817 g
D) 0.829 g
E) 11.4 g

Question 48

A mass of 4.00 g of H₂(g)reacts with 2.00 g of O₂(g).If 1.94 g of H₂O(l)is collected,what is the percent yield of the reaction? 2H₂(g)+ O₂(g)→ 2H₂O(l)

A) 5.4 %
B) 49 %
C) 32 %
D) 86 %
E) 97 %

Question 49

What mass of oxygen will react with 2.64 g of magnesium? 2Mg(s)+ O₂(g)→ MgO(s)

A) 0.487 g
B) 1.00 g
C) 1.26 g
D) 1.74 g
E) 3.47 g

Question 50

The reaction of coal and water at a high temperature produces a mixture of hydrogen and carbon monoxide gases.This mixture is known as synthesis gas (or syngas).What mass of carbon monoxide can be formed from the reaction of 71.3 g of carbon with excess water? C(s)+ H₂O(g)→ H₂(g)+ CO(g)

A) 5.94 g
B) 12.0 g
C) 71.3 g
D) 107 g
E) 166 g

Question 51

Which of the balanced chemical equations is consistent with the following pictorial representation of a chemical reaction?

A) 2SO₂ + O₂ → 2SO₃
B) H₂ + I₂ → 2HI
C) 2H₂ + O₂ → 2H₂O
D) 2N₂ + 3H₂ → 2NH₃
E) none of the above

Question 52

How many moles of ammonia can be made by reacting 7.0 mol of N₂ with 4.0 mol of H₂? N₂(g)+ 3H₂(g)→ 2NH₃(g)

A) 2.7 mol
B) 4.0 mol
C) 7.0 mol
D) 11 mol
E) 14 mol

Question 53

What is the balanced chemical equation for the complete combustion of benzoic acid,C₆H₅CO₂H,to form carbon dioxide and water?

A) C₆H₅CO₂H(s)→ 6C(s)+ CO₂(g)+ 3H₂(g)
B) C₆H₅CO₂H(s)→ 7CO₂(g)+ 3H₂O(g)
C) C₆H₅CO₂H(s)+ O₂(g)→ CO₂(g)+ H₂O(g)
D) C₆H₅CO₂H(s)+ 8O₂(g)→ 7CO₂(g)+ 3H₂O(g)
E) 2C₆H₅CO₂H(s)+ 15O₂(g)→ 14CO₂(g)+ 6H₂O(g)

Question 54

Chlorophyll,the substance responsible for the green color of leaves,has one magnesium atom per chlorophyll molecule and contains 2.72% magnesium by mass.What is the molar mass of chlorophyll?

A) 24.3 g/mol
B) 20.2 g/mol
C) 2020 g/mol
D) 8.94 g/mol
E) 894 g/mol

Question 55

Aluminum reacts in air with oxygen to form aluminum oxide.Which of the reactions below is correct and properly balanced?

A) Al(s)+ O(g)→ AlO(s)
B) 2Al(s)+ O₂(g)→ 2AlO(s)
C) 3Al(s)+ O₂(g)→ Al₃O₂(s)
D) 4Al(s)+ O₂(g)→ 2Al₂O(s)
E) 4Al(s)+ 3O₂(g)→ 2Al₂O₃(s)

Question 56

Nitric oxide is made from the oxidation of ammonia.What mass of nitric oxide can be made from the reaction of 8.00 g NH₃ with 17.0 g O₂? 4NH₃(g)+ 5O₂(g)→ 4NO(g)+ 6H₂O(g)

A) 4.54 g
B) 12.8 g
C) 14.1 g
D) 15.9 g
E) 25.0 g