Question 1

For the following balanced reaction,which of the following is a gas? 2 Na(l)+ Cl2(g)→ 2 NaCl(s)

Accepted Answer

A) Na 
B) 2 Na 
C) Cl2 
D) Cl 
E) NaCl 
A) Na 
B) 2 Na 
C) Cl2 
D) Cl 
E) NaCl

Question 2

How is Avogadro's number related to the numbers on the periodic table?

Accepted Answer

A) The atomic mass listed is the mass of Avogadro's number's worth of atoms. 
B) The masses are all divisible by Avogadro's number,which gives you the weight of one mole. 
C) The periodic table tells you the mass of one atom.From that,and Avogadro's number you know the number of moles. 
D) The periodic table only gives us atomic numbers,not atomic mass. 
E) The mass listed is Avogadro's number. 
A) The atomic mass listed is the mass of Avogadro's number's worth of atoms. 
B) The masses are all divisible by Avogadro's number,which gives you the weight of one mole. 
C) The periodic table tells you the mass of one atom.From that,and Avogadro's number you know the number of moles. 
D) The periodic table only gives us atomic numbers,not atomic mass. 
E) The mass listed is Avogadro's number.

Question 3

The ________ is what needs to be overcome in a reaction so that it can proceed to the products.

Accepted Answer

A) activation energy 
B) catalyst 
C) entropy 
D) thermodynamics 
E) bond energy 
A) activation energy 
B) catalyst 
C) entropy 
D) thermodynamics 
E) bond energy

Question 4

Use the bond energies below to determine whether the following reaction is exothermic or endothermic: $\mathrm { H } _ { 2 }$ + $\mathrm { Cl } _ { 2 }$ ? 2 HCl H-H (bond energy: 436 kJ/mol)
Cl-Cl (bond energy: 243 kJ/mol)
H-Cl (bond energy: 431 kJ/mol)

Accepted Answer

A) Exothermic with more than 50 kJ of energy released. 
B) Endothermic with more than 50 kJ of energy absorbed. 
C) Exothermic with less than 50 kJ of energy released. 
D) Endothermic with less than 50 kJ of energy absorbed. 
A) Exothermic with more than 50 kJ of energy released. 
B) Endothermic with more than 50 kJ of energy absorbed. 
C) Exothermic with less than 50 kJ of energy released. 
D) Endothermic with less than 50 kJ of energy absorbed.

Question 5

If the relative mass of a hydrogen atom is 1/4 that of a helium atom,how many hydrogen atoms would you need to equal the mass of four helium atoms?

Accepted Answer

A) 16 
B) 4 
C) 1/4 
D) 25 
E) 6.022 × 1023 
A) 16 
B) 4 
C) 1/4 
D) 25 
E) 6.022 × 1023

Question 6

If the relative mass of a pingpong ball is 1/20 that of a golf ball,how many golf balls would you need to equal the mass of 200 pingpong balls?

Accepted Answer

A) 10 
B) 200 
C) 100 
D) 20 
E) 6.022 × 1023 
A) 10 
B) 200 
C) 100 
D) 20 
E) 6.022 × 1023

Question 7

What is the number of grams of CO2 produced if you combust 0.50 mole of CH4 according to the following balanced equation? CH4 + 2 O2 → CO2 + 2 H2O

Accepted Answer

A) 22 g 
B) 10 g 
C) 44 g 
D) 32 g 
E) 1 g 
A) 22 g 
B) 10 g 
C) 44 g 
D) 32 g 
E) 1 g

Question 8

-Given that the above energy profiles have the same scale,which of the reactions is the most exothermic?

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) none of the above 
A) a 
B) b 
C) c 
D) d 
E) none of the above

Question 9

What is a reaction rate?

Accepted Answer

A) It is the speed at which reactants are consumed or product is formed. 
B) It is the balanced chemical formula that relates the number of product molecules to reactant molecules. 
C) It is the ratio of the masses of products and reactants. 
D) It is the ratio of the molecular masses of the elements in a given compound. 
E) none of the above 
A) It is the speed at which reactants are consumed or product is formed. 
B) It is the balanced chemical formula that relates the number of product molecules to reactant molecules. 
C) It is the ratio of the masses of products and reactants. 
D) It is the ratio of the molecular masses of the elements in a given compound. 
E) none of the above

Question 10

Why might increasing the concentration of a set of reactants increase the rate of reaction?

Accepted Answer

A) You have increased the chances that any two reactant molecules will collide and react. 
B) You have increased the ratio of reactants to products. 
C) The concentration of reactants is unrelated to the rate of reaction. 
D) The rate of reaction depends only on the mass of the atoms and therefore increases as you increase the mass of the reactants. 
E) none of the above 
A) You have increased the chances that any two reactant molecules will collide and react. 
B) You have increased the ratio of reactants to products. 
C) The concentration of reactants is unrelated to the rate of reaction. 
D) The rate of reaction depends only on the mass of the atoms and therefore increases as you increase the mass of the reactants. 
E) none of the above

Question 11

Which of the following has the greatest mass?

Accepted Answer

A) 1 mole of Pb 
B) 1 mole of H2 
C) 1 mole of Be 
D) 1 mole of Na 
E) All have the same mass. 
A) 1 mole of Pb 
B) 1 mole of H2 
C) 1 mole of Be 
D) 1 mole of Na 
E) All have the same mass.

Question 12

For the following balanced reaction,which of the following is a solid? 2 Na(l)+ Cl2(g)→ 2 NaCl(s)

Accepted Answer

A) Na 
B) 2 Na 
C) Cl2 
D) Cl 
E) NaCl 
A) Na 
B) 2 Na 
C) Cl2 
D) Cl 
E) NaCl

Question 13

What coefficients balance the following equation? ________ $\mathrm { P } _ { 4 }$ (s)+ ________ $\mathrm { H } _ { 2 }$ (g)? ________ P $\mathrm { H } _ { 3 }$ (g)

Accepted Answer

A) 4,2,3 
B) 1,6,4 
C) 1,4,4 
D) 2,10,8 
A) 4,2,3 
B) 1,6,4 
C) 1,4,4 
D) 2,10,8

Question 14

What is an endothermic reaction?

Accepted Answer

A) It is a reaction that requires heat as a reactant. 
B) It is a reaction where the products have more energy than the reactants. 
C) It is a reaction where there is a net adsorption of energy from a reaction. 
D) all of the above 
E) none of the above 
A) It is a reaction that requires heat as a reactant. 
B) It is a reaction where the products have more energy than the reactants. 
C) It is a reaction where there is a net adsorption of energy from a reaction. 
D) all of the above 
E) none of the above

Question 15

How does formula mass differ from atomic mass?

Accepted Answer

A) They represent the same thing. 
B) The formula mass of a substance is the sum of the atomic masses of the elements is its chemical formula.The atomic mass is the mass of a single atom. 
C) The atomic mass of a substance is the sum of the formula masses of the elements is its chemical formula.The atomic mass is the mass of a single atom. 
D) The formula mass is the mass of the chemical formula and the atomic mass is the mass of the molecule. 
A) They represent the same thing. 
B) The formula mass of a substance is the sum of the atomic masses of the elements is its chemical formula.The atomic mass is the mass of a single atom. 
C) The atomic mass of a substance is the sum of the formula masses of the elements is its chemical formula.The atomic mass is the mass of a single atom. 
D) The formula mass is the mass of the chemical formula and the atomic mass is the mass of the molecule.

Question 16

Balance these equations. ________ $\mathrm { H } _ { 2 }$ (g)+ ________ $\mathrm { N } _ { 2 }$ (g)? ________ N $\mathrm { H } _ { 3 }$ (g)

Accepted Answer

A) 2,2,3 
B) 2,2,5 
C) 3,3,2 
D) 3,1,2 
A) 2,2,3 
B) 2,2,5 
C) 3,3,2 
D) 3,1,2

Question 17

Wild plants readily grow "all by themselves" yet the molecules of the growing plant have less entropy than the materials used to make the plant.How is it possible for a there to be this decrease in entropy for a process that occurs all by itself?

Accepted Answer

A) A decrease in entropy does not necessarily mean that a reaction if favored to proceed on its own.It happens in this instance but not in others. 
B) There is no decrease in entropy when wild plants grow.All growing plants tend to display an increase in entropy. 
C) Wild plants don't grow "all by themselves." When we consider the entire system,including the sun,we find an overall increase in entropy. 
D) Life on Earth "arises on its own." It does not depend on entropy processes. 
A) A decrease in entropy does not necessarily mean that a reaction if favored to proceed on its own.It happens in this instance but not in others. 
B) There is no decrease in entropy when wild plants grow.All growing plants tend to display an increase in entropy. 
C) Wild plants don't grow "all by themselves." When we consider the entire system,including the sun,we find an overall increase in entropy. 
D) Life on Earth "arises on its own." It does not depend on entropy processes.

Question 18

-Given the following energy profiles,which of the following reactions is endothermic?   R= reactants P = products

Accepted Answer

A) a 
B) b 
C) c 
D) d 
E) none of the above 
A) a 
B) b 
C) c 
D) d 
E) none of the above

Question 19

Balance the following chemical equation. ________ N2 + ________ H2 → ________ NH3

Accepted Answer

A) 1,3,2 
B) 1,2,3 
C) 3,2,1 
D) 2,6,4 
E) 1/2,3/2,1 
A) 1,3,2 
B) 1,2,3 
C) 3,2,1 
D) 2,6,4 
E) 1/2,3/2,1

Question 20

Since some of the compounds that are destroying ozone are found in nature normally,how is it possible to tell that the reactive molecules destroying the ozone are due to our actions?

Accepted Answer

A) They are accompanied by compounds that are only man-made. 
B) The compounds only increased in the past few years. 
C) The isotope distribution is unique to man-made elements. 
D) The chemical composition is different than natural compounds. 
E) all of the above 
A) They are accompanied by compounds that are only man-made. 
B) The compounds only increased in the past few years. 
C) The isotope distribution is unique to man-made elements. 
D) The chemical composition is different than natural compounds. 
E) all of the above

Exam 17: How Chemicals React

For the following balanced reaction,which of the following is a gas? 2 Na(l)+ Cl2(g)→ 2 NaCl(s)

How is Avogadro's number related to the numbers on the periodic table?

The ________ is what needs to be overcome in a reaction so that it can proceed to the products.

Use the bond energies below to determine whether the following reaction is exothermic or endothermic: H2\mathrm { H } _ { 2 }H2​ + Cl2\mathrm { Cl } _ { 2 }Cl2​ ? 2 HCl H-H (bond energy: 436 kJ/mol) Cl-Cl (bond energy: 243 kJ/mol) H-Cl (bond energy: 431 kJ/mol)

If the relative mass of a hydrogen atom is 1/4 that of a helium atom,how many hydrogen atoms would you need to equal the mass of four helium atoms?

If the relative mass of a pingpong ball is 1/20 that of a golf ball,how many golf balls would you need to equal the mass of 200 pingpong balls?

What is the number of grams of CO2 produced if you combust 0.50 mole of CH4 according to the following balanced equation? CH4 + 2 O2 → CO2 + 2 H2O

-Given that the above energy profiles have the same scale,which of the reactions is the most exothermic?

What is a reaction rate?

Why might increasing the concentration of a set of reactants increase the rate of reaction?

Which of the following has the greatest mass?

For the following balanced reaction,which of the following is a solid? 2 Na(l)+ Cl2(g)→ 2 NaCl(s)

What coefficients balance the following equation? ________ P4\mathrm { P } _ { 4 }P4​ (s)+ ________ H2\mathrm { H } _ { 2 }H2​ (g)? ________ P H3\mathrm { H } _ { 3 }H3​ (g)

What is an endothermic reaction?

How does formula mass differ from atomic mass?

Balance these equations. ________ H2\mathrm { H } _ { 2 }H2​ (g)+ ________ N2\mathrm { N } _ { 2 }N2​ (g)? ________ N H3\mathrm { H } _ { 3 }H3​ (g)

Wild plants readily grow "all by themselves" yet the molecules of the growing plant have less entropy than the materials used to make the plant.How is it possible for a there to be this decrease in entropy for a process that occurs all by itself?

-Given the following energy profiles,which of the following reactions is endothermic? R= reactants P = products

Balance the following chemical equation. ________ N2 + ________ H2 → ________ NH3

Since some of the compounds that are destroying ozone are found in nature normally,how is it possible to tell that the reactive molecules destroying the ozone are due to our actions?

Patterns of Motion and Equilibrium

Newtons Laws of Motion

Momentum and Energy

Gravity, Projectiles, and Satellites

Fluid Mechanics

Thermal Energy and Thermodynamics

Heat Transfer and Change of Phase

Static and Current Electricity

Magnetism and Electromagnetic Induction

Waves and Sound

Light

Atoms and the Periodic Table

The Atomic Nucleus and Radioactivity

Elements of Chemistry

How Atoms Bond and Molecules Attract

Mixtures

Two Classes of Chemical Reactions

Organic Compounds

Rocks and Minerals

Plate Tectonics and Earths Interior

Shaping Earths Surface

Geologic Time - Reading the Rock Record

The Oceans, Atmosphere, and Climatic Effects

Driving Forces of Weather

The Solar System

Stars and Galaxies

The Structure of Space and Time

Prologue: The Nature of Science

Filters

For the following balanced reaction,which of the following is a gas? 2 Na(l)+ Cl₂(g)→ 2 NaCl(s)

Use the bond energies below to determine whether the following reaction is exothermic or endothermic: $\mathrm { H } _ { 2 }$ + $\mathrm { Cl } _ { 2 }$ ? 2 HCl H-H (bond energy: 436 kJ/mol) Cl-Cl (bond energy: 243 kJ/mol) H-Cl (bond energy: 431 kJ/mol)

What is the number of grams of CO₂ produced if you combust 0.50 mole of CH₄ according to the following balanced equation? CH₄ + 2 O₂ → CO₂ + 2 H₂O

For the following balanced reaction,which of the following is a solid? 2 Na(l)+ Cl₂(g)→ 2 NaCl(s)

What coefficients balance the following equation? ________ $\mathrm { P } _ { 4 }$ (s)+ ________ $\mathrm { H } _ { 2 }$ (g)? ________ P $\mathrm { H } _ { 3 }$ (g)

Balance these equations. ________ $\mathrm { H } _ { 2 }$ (g)+ ________ $\mathrm { N } _ { 2 }$ (g)? ________ N $\mathrm { H } _ { 3 }$ (g)

Balance the following chemical equation. N₂ + H₂ → NH₃