Question 1

An acid and a base react to form a salt,which consists of positive and negative ions.Which forms the positive ions: the acid or the base? Which forms the negative ions?

Accepted Answer

A) The acid forms the positive ion,the base forms the negative ion. 
B) The acid forms the negative ion,the base forms the positive ion. 
C) Because different substances can act as an acid or a base,it depends on the substance you begin with. 
D) all of the above

Question 2

Which of the following statements describes a basic solution?

Accepted Answer

A) [H3O+] > [OH-] 
B) [H3O+] -] 
C) [H3O+] × [OH-] ≠ 1 × 10-14 
D) [H3O+]/[OH-] = 1 × 10-14 
E) [H3O+]/[OH-] = 1

Question 3

Why is the air over an open flame always moist?

Accepted Answer

A) The hot flame vaporizes the water in the air above the flame. 
B) One of the products of combustion is water vapor. 
C) Warm air contains more humidity than cold air. 
D) None of the above is true.

Question 4

How does an atom's electronegativity relate to its ability to become oxidized?

Accepted Answer

A) The greater the electronegativity of an atom,the greater its ability to become oxidized. 
B) The lower the electronegativity of an atom,the lower its ability to become oxidized. 
C) The greater the electronegativity of an atom,the lower its ability to become oxidized. 
D) Electronegativity does not effect the atom's ability to become oxidized.

Question 5

What is the primary difference between a fuel cell and a battery?

Accepted Answer

A) Fuel cells do not run down because they can be refueled; batteries run down and need to be recharged. 
B) Batteries can be recharged,fuel cells cannot. 
C) Batteries supply electricity; fuel cells supply heat. 
D) Fuel cells oxidize to supply electricity,batteries reduce to supply electricity. 
E) Fuel cells do not use metals as oxidants and reductants,batteries have a static reservoir of oxidant and reductant.

Question 6

What happens to the pH of an acidic solution as water is added?

Accepted Answer

A) The pH is not influenced by the addition of water. 
B) The pH will decrease as the solution becomes more dilute. 
C) The pH will increase as the solution becomes more dilute. 
D) The pH will decrease since more hydronium ions are produced from the water.

Question 7

Lakes lying in granite basins,such as those in the northeastern U.S.,tend to become acidified by acid rain more readily than lakes lying in limestone basins,such as those found in the midwestern U.S.Why is this so?

Accepted Answer

A) The granite contains acidic minerals that dissolve in the rain water and are added to the lakes. 
B) Since the acidified water cannot percolate through the granite,the acid in the lakes becomes more concentrated. 
C) The limestone,which is calcium carbonate,serves to neutralize the acid in the rain. 
D) There is more acid rain in the northeast than in the midwestern regions of the U.S.

Question 8

How do you make a proton out of a hydrogen atom?

Accepted Answer

A) remove an electron from a hydrogen atom 
B) remove a proton from a helium nucleus 
C) let the hydrogen atoms undergo fusion 
D) let the hydrogen atoms combine to form a hydrogen molecule and eject an electron 
E) let the hydrogen atoms combine to form a hydrogen molecule and eject a proton

Question 9

Which of the following statements about oxidation and reduction reactions is true?

Accepted Answer

A) More than one electron can be transferred in an oxidation and reduction reaction. 
B) In a half-reaction,only half of an electron is transferred. 
C) Only neutral atoms are formed in oxidation and reduction reactions. 
D) A half-reaction is only used for reduction reactions. 
E) None of the above are true.

Question 10

For the following reaction,identify whether the compound in bold is behaving as an acid or a base. H3PO4 + H2O ⇌ H2PO4- + H3O+

Accepted Answer

A) acid 
B) base 
C) neither 
D) both 
E) none of the above

Question 11

Identify the acid or base behavior of each substance in these reactions: $\mathrm { H } _ { 3 }$ $\mathrm { O } ^ { + }$ + $\mathrm { Cl } ^ { - }$ ? $\mathrm { H } _ { 2 }$ O + HCl

Accepted Answer

A)  $\mathrm { H } _ { 3 }$ $\mathrm { O } ^ { + }$ acts as an acid, $\mathrm { Cl } ^ { - }$ acts as a base, $\mathrm { H } _ { 2 }$ O acts an acid,HCl acts as a base. 
B)  $\mathrm { H } _ { 3 }$ $\mathrm { O } ^ { + }$ acts as an base, $$\mathrm { Cl } ^ { - }$$ acts as a acid, $$\mathrm { H } _ { 2 }$$ O acts an acid,HCl acts as a base. 
C)  $\mathrm { H } _ { 3 }$ $\mathrm { O } ^ { + }$ acts as an acid, $\mathrm { Cl } ^ { - }$ acts as a base, $\mathrm { H } _ { 2 }$ O acts an base,HCl acts as a acid. 
D)  $\mathrm { H } _ { 3 }$ $\mathrm { O } ^ { + }$ acts as an base, $\mathrm { Cl } ^ { - }$ acts as a acid, $\mathrm { H } _ { 2 }$

Question 12

What is the purpose of the salt bridge in a voltaic cell?

Accepted Answer

A) to prevent any further migration of electrons through the wire 
B) to allow for the build up of positively charged ions in one container and negatively charged ions in the other container 
C) to allow the $\mathrm { Fe } ^ { 2 + }$ and the $\mathrm { Cu } ^ { 2 + }$ to flow freely between the two containers 
D) to allow for a balance of charge between the two chambers

Question 13

Which of the following describes an electrode?

Accepted Answer

A) Any material that conducts electrons into a media where electrochemical reactions are taking place. 
B) Any material that conducts electrons out of a media where electrochemical reactions are taking place. 
C) Any material that conducts electrons. 
D) Any material that is undergoing an oxidation-reduction reaction in a battery. 
E) either A or B

Question 14

Which element is closer to the upper right corner of the periodic table,the one indicated by the lighter colored atoms or the darker colored atoms?

Accepted Answer

A) the element indicated by the darker color 
B) the element indicated by the lighter color 
C) More information is needed in order to determine which element is closer to the upper right of the periodic table. 
D) Both the lighter and darker colored elements are likely found at the upper right corner of the periodic table.

Question 15

In a battery,the following oxidation-reduction reaction is taking place: Mn2O3 + ZnO → 2 MnO2 + Zn
What is undergoing reduction as written?

Accepted Answer

A) Zn 
B) ZnO 
C) MnO2 
D) Mn2O3 
E) none of the above

Question 16

As the hydronium ion concentration increases,the pH

Accepted Answer

A) goes down. 
B) gets larger. 
C) starts to affect the OH- concentration. 
D) starts to alter the chemical properties of the water molecules. 
E) stays constant.

Question 17

Which of the following statements describes a neutral solution?

Accepted Answer

A) [H3O+] > [OH-] 
B) [H3O+] -] 
C) [H3O+] × [OH-] ≠ 1 × 10-14 
D) [H3O+]/[OH-] = 1 × 10-14 
E) [H3O+]/[OH-] = 1

Question 18

According to the following reaction,which molecule is acting as an acid? H3O+ + HSO4- → H2O + H2SO4

Accepted Answer

A) H2SO4 
B) H2O 
C) H3O+ 
D) HSO4- 
E) none of the above

Question 19

If you had a 1 M solution of a weak base what would be its pH?

Accepted Answer

A) 1 
B) 6 
C) 7 
D) 8 
E) 13

Question 20

For the following reaction,identify whether the compound in bold is behaving as an acid or a base. H3PO4 + H2O ⇌ H2PO4- + H3O+

Accepted Answer

A) acid 
B) base 
C) neither 
D) both 
E) none of the above

Exam 18: Two Classes of Chemical Reactions

An acid and a base react to form a salt,which consists of positive and negative ions.Which forms the positive ions: the acid or the base? Which forms the negative ions?

Which of the following statements describes a basic solution?

Why is the air over an open flame always moist?

How does an atom's electronegativity relate to its ability to become oxidized?

What is the primary difference between a fuel cell and a battery?

What happens to the pH of an acidic solution as water is added?

Lakes lying in granite basins,such as those in the northeastern U.S.,tend to become acidified by acid rain more readily than lakes lying in limestone basins,such as those found in the midwestern U.S.Why is this so?

How do you make a proton out of a hydrogen atom?

Which of the following statements about oxidation and reduction reactions is true?

For the following reaction,identify whether the compound in bold is behaving as an acid or a base. H₃PO₄ + H₂O ⇌ H₂PO₄^- + H₃O⁺

Identify the acid or base behavior of each substance in these reactions: $\mathrm { H } _ { 3 }$ $\mathrm { O } ^ { + }$ + $\mathrm { Cl } ^ { - }$ ? $\mathrm { H } _ { 2 }$ O + HCl

What is the purpose of the salt bridge in a voltaic cell?

Which of the following describes an electrode?

Which element is closer to the upper right corner of the periodic table,the one indicated by the lighter colored atoms or the darker colored atoms?

In a battery,the following oxidation-reduction reaction is taking place: Mn₂O₃ + ZnO → 2 MnO₂+ Zn What is undergoing reduction as written?

As the hydronium ion concentration increases,the pH

Which of the following statements describes a neutral solution?

According to the following reaction,which molecule is acting as an acid? H₃O⁺ + HSO₄^- → H₂O + H₂SO₄

If you had a 1 M solution of a weak base what would be its pH?

For the following reaction,identify whether the compound in bold is behaving as an acid or a base. H₃PO₄ + H₂O ⇌ H₂PO₄^- + H₃O⁺

Exam 18: Two Classes of Chemical Reactions

An acid and a base react to form a salt,which consists of positive and negative ions.Which forms the positive ions: the acid or the base? Which forms the negative ions?

Which of the following statements describes a basic solution?

Why is the air over an open flame always moist?

How does an atom's electronegativity relate to its ability to become oxidized?

What is the primary difference between a fuel cell and a battery?

What happens to the pH of an acidic solution as water is added?

Lakes lying in granite basins,such as those in the northeastern U.S.,tend to become acidified by acid rain more readily than lakes lying in limestone basins,such as those found in the midwestern U.S.Why is this so?

How do you make a proton out of a hydrogen atom?

Which of the following statements about oxidation and reduction reactions is true?

For the following reaction,identify whether the compound in bold is behaving as an acid or a base. H3PO4 + H2O ⇌ H2PO4- + H3O+

Identify the acid or base behavior of each substance in these reactions: H3\mathrm { H } _ { 3 }H3​ O+\mathrm { O } ^ { + }O+ + Cl−\mathrm { Cl } ^ { - }Cl− ? H2\mathrm { H } _ { 2 }H2​ O + HCl

What is the purpose of the salt bridge in a voltaic cell?

Which of the following describes an electrode?

Which element is closer to the upper right corner of the periodic table,the one indicated by the lighter colored atoms or the darker colored atoms?

In a battery,the following oxidation-reduction reaction is taking place: Mn2O3 + ZnO → 2 MnO2 + Zn What is undergoing reduction as written?

As the hydronium ion concentration increases,the pH

Which of the following statements describes a neutral solution?

According to the following reaction,which molecule is acting as an acid? H3O+ + HSO4- → H2O + H2SO4

If you had a 1 M solution of a weak base what would be its pH?

For the following reaction,identify whether the compound in bold is behaving as an acid or a base. H3PO4 + H2O ⇌ H2PO4- + H3O+

For the following reaction,identify whether the compound in bold is behaving as an acid or a base. H₃PO₄ + H₂O ⇌ H₂PO₄^- + H₃O⁺

Identify the acid or base behavior of each substance in these reactions: $\mathrm { H } _ { 3 }$ $\mathrm { O } ^ { + }$ + $\mathrm { Cl } ^ { - }$ ? $\mathrm { H } _ { 2 }$ O + HCl

In a battery,the following oxidation-reduction reaction is taking place: Mn₂O₃ + ZnO → 2 MnO₂+ Zn What is undergoing reduction as written?

According to the following reaction,which molecule is acting as an acid? H₃O⁺ + HSO₄^- → H₂O + H₂SO₄

For the following reaction,identify whether the compound in bold is behaving as an acid or a base. H₃PO₄ + H₂O ⇌ H₂PO₄^- + H₃O⁺