Question 1

Give the formula for ozone.

Accepted Answer

A) O3 
B) O2 
C) O 
D) H2O2 
E) H2O 
A) O3 
B) O2 
C) O 
D) H2O2 
E) H2O A

Question 2

A mixture of 0.220 moles CO,0.350 moles H2,and 0.640 moles He has a total pressure of 2.989 bar.What is the pressure of H2?

Accepted Answer

A) 1.17 bar 
B) 0.865 bar 
C) 1.03 bar 
D) 0.969 bar 
E) 0.649 bar 
A) 1.17 bar 
B) 0.865 bar 
C) 1.03 bar 
D) 0.969 bar 
E) 0.649 bar B

Question 3

Define the vapour pressure of water.

Accepted Answer

A) partial pressure of water in a liquid mixture 
B) partial pressure of water in a gaseous mixture 
C) condensation of water 
D) water dissolved in a liquid 
E) water molecules 
A) partial pressure of water in a liquid mixture 
B) partial pressure of water in a gaseous mixture 
C) condensation of water 
D) water dissolved in a liquid 
E) water molecules B

Question 4

The action of some commercial drain cleaners is based on the following reaction: 2NaOH(s)+ 2Al(s)+ 6H2O(l)→ 2NaAl(OH)4(s)+ 3H2(g)
What is the volume of H2 gas formed at STP when 6.32 g of Al reacts with excess NaOH?

Accepted Answer

A) 3.50 L 
B) 5.25L 
C) 7.98 L 
D) 8.59L 
A) 3.50 L 
B) 5.25L 
C) 7.98 L 
D) 8.59L

Question 5

A large balloon is initially filled to a volume of 25.0 L at 353 K and a pressure of 2575 mmHg.What volume of gas will the balloon contain at 1.368 bar and 253 K?

Accepted Answer

A) 22.2 L 
B) 87.5 L 
C) 11.4 L 
D) 45.0 L 
E) 58.6 L 
A) 22.2 L 
B) 87.5 L 
C) 11.4 L 
D) 45.0 L 
E) 58.6 L

Question 6

A compound is found to be 30.45% N and 69.55 % O by mass.If 1.63 g of this compound occupy 389 mL at 0.00 °C and 1.0332 bar,what is the molecular formula of the compound?

Accepted Answer

A) NO2 
B) N2O 
C) N4O2 
D) N2O5 
E) N2O4 
A) NO2 
B) N2O 
C) N4O2 
D) N2O5 
E) N2O4

Question 7

Why does hot air rise?

Accepted Answer

As air is heated,it expands an

Question 8

What volume will a balloon occupy at 1.01 bar if the balloon has a volume of 7.6 L at 3.85 bar?

Accepted Answer

A) 2.0 L 
B) 5.0 L 
C) 29 L 
D) 35 L 
E) 17 L 
A) 2.0 L 
B) 5.0 L 
C) 29 L 
D) 35 L 
E) 17 L

Question 9

What volume (in mL)will a sample of F2 gas occupy in a syringe at 5.57 bar if the F2 has a volume of 25.0 mL at 1.22 bar?

Accepted Answer

A) 11 mL 
B) 17 mL 
C) 3.8 mL 
D) 5.5 mL 
E) 7.6 mL 
A) 11 mL 
B) 17 mL 
C) 3.8 mL 
D) 5.5 mL 
E) 7.6 mL

Question 10

The following reaction is used to generate hydrogen gas in the laboratory.If 243 mL of gas is collected at 25 °C and has a total pressure of 0.9933 bar,what mass of hydrogen is produced? A possibly useful table of water vapour pressures is provided below. 
Mg(s)+ 2HCl(aq)→ MgCl2(aq)+ H2(g)
T (°C)$\quad$$\quad$P(bar)
20 $\quad$$\quad$$\quad$0.023398
25 $\quad$$\quad$$\quad$0.031704
30 $\quad$$\quad$$\quad$0.042477

Accepted Answer

A) 0.0196 g H2 
B) 0.0717 g H2 
C) 0.0190 g H2 
D) 0.0144 g H2 
E) 0.0449 g H2 
A) 0.0196 g H2 
B) 0.0717 g H2 
C) 0.0190 g H2 
D) 0.0144 g H2 
E) 0.0449 g H2

Question 11

What pressure would a gas mixture in a 10.0 L tank exert if it were composed of 48.5 g He and 94.6 g CO2 at 398 K?

Accepted Answer

A) 7.11 bar 
B) 39.6 bar 
C) 40.1 bar 
D) 47.2 bar 
E) 58.7 bar 
A) 7.11 bar 
B) 39.6 bar 
C) 40.1 bar 
D) 47.2 bar 
E) 58.7 bar

Question 12

Convert 4744.1 mmHg to bar.

Accepted Answer

A) 7.549 bar 
B) 5.2423 bar 
C) 5.278 bar 
D) 6.817 bar 
E) 6.325 bar 
A) 7.549 bar 
B) 5.2423 bar 
C) 5.278 bar 
D) 6.817 bar 
E) 6.325 bar

Question 13

A gas occupies 3.33 L at 2.23 bar.What is the volume at 2.50 bar?

Accepted Answer

A) 1.67 L 
B) 3.73 L 
C) 2.97 L 
D) 0.268 L 
E) 18.6 L 
A) 1.67 L 
B) 3.73 L 
C) 2.97 L 
D) 0.268 L 
E) 18.6 L

Question 14

How many grams of F2 gas are there in a 5.00 L cylinder at 5.327 bar and 23 °C?

Accepted Answer

A) 19.5 g 
B) 41.1 g 
C) 500 g 
D) 2.96 × 104 g 
A) 19.5 g 
B) 41.1 g 
C) 500 g 
D) 2.96 × 104 g

Question 15

A syringe contains 0.65 moles of He gas that occupy 750.0 mL.What volume (in L)of gas will the syringe hold if 0.35 moles of Ne is added?

Accepted Answer

A) 0.87 L 
B) 4.9 L 
C) 1.2 L 
D) 2.1 L 
E) 1.9 L 
A) 0.87 L 
B) 4.9 L 
C) 1.2 L 
D) 2.1 L 
E) 1.9 L

Question 16

A container filled with gas is connected to an open-end manometer that is filled with mineral oil.The pressure in the gas container is 753 mmHg and atmospheric pressure is 724 mmHg.How high will the level rise in the manometer if the densities of Hg and mineral oil are 13.6 g mL-1 and 0.822 g mL-1,respectively?

Accepted Answer

A) 1.75 mm 
B) 23.8 mm 
C) 29.0 mm 
D) 480 mm 
A) 1.75 mm 
B) 23.8 mm 
C) 29.0 mm 
D) 480 mm

Question 17

A syringe contains 589 mL of CO at 325 K and 1.2 bar.A second syringe contains 473 mL of N2 at 298 K and 2.6 bar.What is the final pressure if the contents of these two syringes are injected into a 1.00 L container at 273 K?

Accepted Answer

A) 0.59 bar 
B) 1.1 bar 
C) 1.7 bar 
D) 1.9 bar 
E) 3.8 bar 
A) 0.59 bar 
B) 1.1 bar 
C) 1.7 bar 
D) 1.9 bar 
E) 3.8 bar

Question 18

Determine the theoretical yield and the percent yield if 21.8 g of K2CO3 is produced from reacting 27.9 g KO2 with 29.0 L of CO2 (at STP).The molar mass of KO2 is 71.10 g mol-1 and K2CO3 is 138.21 g mol-1. 
4KO2(s)+ 2CO2(g)→ 2K2CO3(s)+ 3O2(g)

Accepted Answer

A) 27.1 g,80.4% yield 
B) 179 g,12.2% yield 
C) 91.7 g,23.8% yield 
D) 206 g,10.6% yield 
E) 61.0 g,35.7% yield 
A) 27.1 g,80.4% yield 
B) 179 g,12.2% yield 
C) 91.7 g,23.8% yield 
D) 206 g,10.6% yield 
E) 61.0 g,35.7% yield

Question 19

How many grams of calcium hydride are required to produce 4.56 L of hydrogen gas at 25.0 °C and 0.975 bar according to the chemical equation shown below? CaH2(s)+ 2H2O(l)→ Ca(OH)2(aq)+ 2H2(g)

Accepted Answer

A) 3.77 g 
B) 7.64 g 
C) 15.3 g 
D) 45.6 g 
A) 3.77 g 
B) 7.64 g 
C) 15.3 g 
D) 45.6 g

Question 20

Which of the following samples has the greatest density at STP?

Accepted Answer

A) NO2 
B) Xe 
C) SO2 
D) SF6 
E) All of these samples have the same density at STP. 
A) NO2 
B) Xe 
C) SO2 
D) SF6 
E) All of these samples have the same density at STP.

Exam 5: Gases

Give the formula for ozone.

A mixture of 0.220 moles CO,0.350 moles H2,and 0.640 moles He has a total pressure of 2.989 bar.What is the pressure of H2?

Define the vapour pressure of water.

The action of some commercial drain cleaners is based on the following reaction: 2NaOH(s)+ 2Al(s)+ 6H2O(l)→ 2NaAl(OH)4(s)+ 3H2(g) What is the volume of H2 gas formed at STP when 6.32 g of Al reacts with excess NaOH?

A large balloon is initially filled to a volume of 25.0 L at 353 K and a pressure of 2575 mmHg.What volume of gas will the balloon contain at 1.368 bar and 253 K?

A compound is found to be 30.45% N and 69.55 % O by mass.If 1.63 g of this compound occupy 389 mL at 0.00 °C and 1.0332 bar,what is the molecular formula of the compound?

Why does hot air rise?

What volume will a balloon occupy at 1.01 bar if the balloon has a volume of 7.6 L at 3.85 bar?

What volume (in mL)will a sample of F2 gas occupy in a syringe at 5.57 bar if the F2 has a volume of 25.0 mL at 1.22 bar?

What pressure would a gas mixture in a 10.0 L tank exert if it were composed of 48.5 g He and 94.6 g CO2 at 398 K?

Convert 4744.1 mmHg to bar.

A gas occupies 3.33 L at 2.23 bar.What is the volume at 2.50 bar?

How many grams of F2 gas are there in a 5.00 L cylinder at 5.327 bar and 23 °C?

A syringe contains 0.65 moles of He gas that occupy 750.0 mL.What volume (in L)of gas will the syringe hold if 0.35 moles of Ne is added?

A syringe contains 589 mL of CO at 325 K and 1.2 bar.A second syringe contains 473 mL of N2 at 298 K and 2.6 bar.What is the final pressure if the contents of these two syringes are injected into a 1.00 L container at 273 K?

Determine the theoretical yield and the percent yield if 21.8 g of K2CO3 is produced from reacting 27.9 g KO2 with 29.0 L of CO2 (at STP).The molar mass of KO2 is 71.10 g mol-1 and K2CO3 is 138.21 g mol-1. 4KO2(s)+ 2CO2(g)→ 2K2CO3(s)+ 3O2(g)

How many grams of calcium hydride are required to produce 4.56 L of hydrogen gas at 25.0 °C and 0.975 bar according to the chemical equation shown below? CaH2(s)+ 2H2O(l)→ Ca(OH)2(aq)+ 2H2(g)

Which of the following samples has the greatest density at STP?

Units of Measurement for Physical and Chemical Change

Atoms and Elements

Molecules,compounds,and Nomenclature

Chemical Reactions and Stoichiometry

Thermochemistry

The Quantum-Mechanical Model of the Atom

Periodic Properties of the Elements

Chemical Bonding I: Lewis Theory

Chemical Bonding II: Molecular Shapes, valence Bond Theory, and Molecular Orbital Theory

Liquids, solids, and Intermolecular Forces

Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Aqueous Ionic Equilibrium

Gibbs Energy and Thermodynamics

Electrochemistry

Radioactivity and Nuclear Chemistry

Organic Chemistry I: Structures

Organic Chemistry II: Reactions

Biochemistry

Chemistry of the Nonmetals

Metals and Metallurgy

Transition Metals and Coordination Compounds

Filters

A mixture of 0.220 moles CO,0.350 moles H₂,and 0.640 moles He has a total pressure of 2.989 bar.What is the pressure of H₂?

The action of some commercial drain cleaners is based on the following reaction: 2NaOH(s)+ 2Al(s)+ 6H₂O(l)→ 2NaAl(OH)₄(s)+ 3H₂(g) What is the volume of H₂ gas formed at STP when 6.32 g of Al reacts with excess NaOH?

What volume (in mL)will a sample of F₂ gas occupy in a syringe at 5.57 bar if the F₂ has a volume of 25.0 mL at 1.22 bar?

What pressure would a gas mixture in a 10.0 L tank exert if it were composed of 48.5 g He and 94.6 g CO₂ at 398 K?

How many grams of F₂ gas are there in a 5.00 L cylinder at 5.327 bar and 23 °C?

A syringe contains 589 mL of CO at 325 K and 1.2 bar.A second syringe contains 473 mL of N₂ at 298 K and 2.6 bar.What is the final pressure if the contents of these two syringes are injected into a 1.00 L container at 273 K?

Determine the theoretical yield and the percent yield if 21.8 g of K₂CO₃ is produced from reacting 27.9 g KO₂ with 29.0 L of CO₂ (at STP).The molar mass of KO₂ is 71.10 g mol^-1 and K₂CO₃is 138.21 g mol^-1. 4KO₂(s)+ 2CO₂(g)→ 2K₂CO₃(s)+ 3O₂(g)

How many grams of calcium hydride are required to produce 4.56 L of hydrogen gas at 25.0 °C and 0.975 bar according to the chemical equation shown below? CaH₂(s)+ 2H₂O(l)→ Ca(OH)₂(aq)+ 2H₂(g)