Question 1

Two amu equals how many grams?

Accepted Answer

A) 2 grams 
B) 1.661 × 10-24 grams 
C) 3.322 × 10-24 grams 
D) 1.204 × 10-22 grams 
A) 2 grams 
B) 1.661 × 10-24 grams 
C) 3.322 × 10-24 grams 
D) 1.204 × 10-22 grams

Question 2

The yeast in bread dough feeds on sugar to produce carbon dioxide. Why does the dough rise faster in a warmer area?

Accepted Answer

A) There is a greater number of effective collisions among reacting molecules. 
B) Atmospheric pressure decreases with increasing temperature. 
C) The yeast tends to "wake up" with warmer temperatures, which is why baker's yeast is best stored in the refrigerator. 
D) The rate of evaporation increases with increasing temperature. 
A) There is a greater number of effective collisions among reacting molecules. 
B) Atmospheric pressure decreases with increasing temperature. 
C) The yeast tends to "wake up" with warmer temperatures, which is why baker's yeast is best stored in the refrigerator. 
D) The rate of evaporation increases with increasing temperature.

Question 3

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

Accepted Answer

A) 2 moles 
B) 4 moles 
C) 6 moles 
D) 8 moles 
E) 1 mole 
A) 2 moles 
B) 4 moles 
C) 6 moles 
D) 8 moles 
E) 1 mole

Question 4

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 5

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 6

Are the chemical reactions that take place in a disposable battery exothermic or endothermic? Is the reaction going on in a rechargeable battery while it is recharging exothermic or endothermic?

Accepted Answer

A) An operating disposable battery is driven by endothermic reaction, while a recharging rechargeable battery is also driven by endothermic reactions. 
B) An operating disposable battery is driven by exothermic reaction, while a recharging rechargeable battery is driven by endothermic reactions. 
C) An operating disposable battery is driven by endothermic reaction, while a recharging rechargeable battery is driven by exothermic reactions. 
D) An operating disposable battery is driven by exothermic reaction, while a recharging rechargeable battery is also driven by exothermic reactions. 
A) An operating disposable battery is driven by endothermic reaction, while a recharging rechargeable battery is also driven by endothermic reactions. 
B) An operating disposable battery is driven by exothermic reaction, while a recharging rechargeable battery is driven by endothermic reactions. 
C) An operating disposable battery is driven by endothermic reaction, while a recharging rechargeable battery is driven by exothermic reactions. 
D) An operating disposable battery is driven by exothermic reaction, while a recharging rechargeable battery is also driven by exothermic reactions.

Question 7

Which is greater: 1.01 amu of hydrogen or 1.01 grams of hydrogen?

Accepted Answer

A) 1.01 amu of hydrogen is greater than 1.01 grams of hydrogen. 
B) 1.01 grams of hydrogen is greater than 1.01 amu of hydrogen 
C) 1.01 grams of hydrogen and 1.01 amu of hydrogen have the same mass. 
D) Not enough information information is provided. 
A) 1.01 amu of hydrogen is greater than 1.01 grams of hydrogen. 
B) 1.01 grams of hydrogen is greater than 1.01 amu of hydrogen 
C) 1.01 grams of hydrogen and 1.01 amu of hydrogen have the same mass. 
D) Not enough information information is provided.

Question 8

Which of the following statements about catalysts is NOT true?

Accepted Answer

A) A catalyst alters the rate of a chemical reaction. 
B) A catalyst can be consumed in a reaction as long as it is regenerated. 
C) A catalyst can be used to speed up slow reactions. 
D) A catalyst does not change the energy of the reactants or the products. 
E) All of the above are true. 
A) A catalyst alters the rate of a chemical reaction. 
B) A catalyst can be consumed in a reaction as long as it is regenerated. 
C) A catalyst can be used to speed up slow reactions. 
D) A catalyst does not change the energy of the reactants or the products. 
E) All of the above are true.

Question 9

The portion of the atmosphere that filters out 95 percent of the incident UV radiation is the ________.

Accepted Answer

A) ozone layer 
B) stratosphere 
C) troposphere 
D) aerosol layer 
E) particulates 
A) ozone layer 
B) stratosphere 
C) troposphere 
D) aerosol layer 
E) particulates

Question 10

Which of the following statements about ozone is true?

Accepted Answer

A) Ozone in the stratosphere is beneficial. 
B) Ozone in the troposphere is a pollutant. 
C) Ozone is generated from photochemical reactions of hydrocarbons. 
D) none of the above 
E) both a and b 
A) Ozone in the stratosphere is beneficial. 
B) Ozone in the troposphere is a pollutant. 
C) Ozone is generated from photochemical reactions of hydrocarbons. 
D) none of the above 
E) both a and b

Question 11

What can you deduce about the activation energy of a reaction that takes billions of years to go to completion? How about a reaction that takes only fractions of a second?

Accepted Answer

A) The activation energy of both these reactions must be very low. 
B) The activation energy of both these reactions must be very high. 
C) The slow reaction must have a high activation energy while the fast reaction must have a low activation energy. 
D) The slow reaction must have a low activation energy while the fast reaction must have a high activation energy. 
A) The activation energy of both these reactions must be very low. 
B) The activation energy of both these reactions must be very high. 
C) The slow reaction must have a high activation energy while the fast reaction must have a low activation energy. 
D) The slow reaction must have a low activation energy while the fast reaction must have a high activation energy.

Question 12

You are given two samples of elements, and each sample has a mass of 10 grams. If the number of atoms in each of these samples is the same, what must be true of the two elements?

Accepted Answer

A) The density of the two elements are the same. 
B) The elements are likely be located in the same position in the periodic table. 
C) Their spectral patterns will likely be identical. 
D) all of the above 
A) The density of the two elements are the same. 
B) The elements are likely be located in the same position in the periodic table. 
C) Their spectral patterns will likely be identical. 
D) all of the above

Question 13

Which has the greatest number of molecules?

Accepted Answer

A) 28 g of nitrogen, N2 
B) 32 g of oxygen, O2 
C) 32 g of methane, C H4 
D) 38 g of fluorine, F2 
A) 28 g of nitrogen, N2 
B) 32 g of oxygen, O2 
C) 32 g of methane, C H4 
D) 38 g of fluorine, F2

Question 14

Which is higher in an endothermic reaction: the potential energy of the reactants or the potential energy of the products?

Accepted Answer

A) The potential energy of the products is higher than the potential energy of the reactants. 
B) The potential energy of the reactants is higher than the potential energy of the products. 
C) The potential energy of the reactants is the same as the potential energy of the products. 
D) In the early stages of the reaction the potential energy of the reactants is higher. In the later stages, the potential energy of the products is higher. 
A) The potential energy of the products is higher than the potential energy of the reactants. 
B) The potential energy of the reactants is higher than the potential energy of the products. 
C) The potential energy of the reactants is the same as the potential energy of the products. 
D) In the early stages of the reaction the potential energy of the reactants is higher. In the later stages, the potential energy of the products is higher.

Question 15

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 16

Which of the following has the greatest number of particles?

Accepted Answer

A) 1 mole of Na 
B) 22.990 g of Na 
C) 1 mole of Be 
D) 9.012 g of Be 
E) All are the same. 
A) 1 mole of Na 
B) 22.990 g of Na 
C) 1 mole of Be 
D) 9.012 g of Be 
E) All are the same.

Question 17

Given that the bond energy of N2 is 946 kJ/mole, the bond energy of O2 is 498 kJ/mole and the NO bond energy is 631 kJ/mole, how much energy is required to react 1 mole of nitrogen molecules according to the following reaction? N2 + O2 → 2 NO

Accepted Answer

A) 182 kJ 
B) -182 kJ 
C) 813 kJ 
D) -813 kJ 
E) 2075 kJ 
A) 182 kJ 
B) -182 kJ 
C) 813 kJ 
D) -813 kJ 
E) 2075 kJ

Question 18

Given the following generic chemical reaction, which is the product? X → Y

Accepted Answer

A) Y is the product. 
B) X is the product. 
C) → is the product. 
D) Both X and Y are the products. 
E) Both X and Y are the reactants. 
A) Y is the product. 
B) X is the product. 
C) → is the product. 
D) Both X and Y are the products. 
E) Both X and Y are the reactants.

Question 19

The chlorinated fluorocarbons molecules are acting as a(n)________ by converting hundreds of thousands of molecules before they are inactivated.

Accepted Answer

A) catalyst 
B) aerosol 
C) active site 
D) acid 
E) base 
A) catalyst 
B) aerosol 
C) active site 
D) acid 
E) base

Question 20

How many grams of water can be produced from the combination of 25.0 grams of hydrogen and 225 grams of oxygen?

Accepted Answer

A) 250 grams 
B) 225 grams 
C) 200 grams 
D) 25 grams 
A) 250 grams 
B) 225 grams 
C) 200 grams 
D) 25 grams

Exam 17: How Chemicals React

Two amu equals how many grams?

The yeast in bread dough feeds on sugar to produce carbon dioxide. Why does the dough rise faster in a warmer area?

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

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

What is a reaction rate?

Are the chemical reactions that take place in a disposable battery exothermic or endothermic? Is the reaction going on in a rechargeable battery while it is recharging exothermic or endothermic?

Which is greater: 1.01 amu of hydrogen or 1.01 grams of hydrogen?

Which of the following statements about catalysts is NOT true?

The portion of the atmosphere that filters out 95 percent of the incident UV radiation is the ________.

Which of the following statements about ozone is true?

What can you deduce about the activation energy of a reaction that takes billions of years to go to completion? How about a reaction that takes only fractions of a second?

You are given two samples of elements, and each sample has a mass of 10 grams. If the number of atoms in each of these samples is the same, what must be true of the two elements?

Which has the greatest number of molecules?

Which is higher in an endothermic reaction: the potential energy of the reactants or the potential energy of the products?

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

Which of the following has the greatest number of particles?

Given that the bond energy of N2 is 946 kJ/mole, the bond energy of O2 is 498 kJ/mole and the NO bond energy is 631 kJ/mole, how much energy is required to react 1 mole of nitrogen molecules according to the following reaction? N2 + O2 → 2 NO

Given the following generic chemical reaction, which is the product? X → Y

The chlorinated fluorocarbons molecules are acting as a(n)________ by converting hundreds of thousands of molecules before they are inactivated.

How many grams of water can be produced from the combination of 25.0 grams of hydrogen and 225 grams of oxygen?

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 Timereading 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

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

Given that the bond energy of N₂ is 946 kJ/mole, the bond energy of O₂ is 498 kJ/mole and the NO bond energy is 631 kJ/mole, how much energy is required to react 1 mole of nitrogen molecules according to the following reaction? N₂ + O₂ → 2 NO