Chemical Reactions

Question 1

Which of the following is an oxidizing agent?

Select one:

a. oxygen
b. hydrogen
c. water
d. hydrogen chloride

Answer 1

a. oxygen

Question 2

In the equation for an endothermic reaction, the word “heat” appears

Select one:

a. on the right side.
b. on the left side.
c. on both sides.
d. on neither side.

Answer 2

b. on the left side.

Question 3

Double replacement or metathesis reactions are generally also

Select one:

a. redox reactions
b. nonredox reactions
c. combination reactions
d. decomposition reactions

Answer 3

b. nonredox reactions

Question 4

What is the oxidation number of Mn in KMnO4?

Select one:

a. +9
b. +5
c. +7
d. +4

Answer 4

c. +7

Question 5

What is the oxidation number of Cl in HClO3?

Select one:

a. +2
b. +3
c. +4
d. +5

Answer 5

d. +5

Question 6

What is the oxidation number of Br in BrO2- ?

Select one:

a. -1
b. +1
c. +2
d. +3

Answer 6

d. +3

Question 7

In which of the following does an element have an oxidation number of +4?

Select one:

a. TiO2
b. HBr
c. SO3
d. SO4-

Answer 7

a. TiO2

Question 8

Which of the following contains the metal with the highest oxidation number?

Select one:

a. CaCl2
b. NaCl
c. FeCl3
d. CuCl2

Answer 8

c. FeCl3

Question 9

A redox reaction can also be a

Select one:

a. combination reaction.
b. single replacement reaction.
c. decomposition reaction.
d. more than one response is correct

Answer 9

d. more than one response is correct

Question 10

The energy involved in chemical reactions

Select one:

a. always appears as heat.
b. always appears as light.
c. always appears as electricity.
d. can take many forms.

Answer 10

d. can take many forms.

Question 11

According to the law of conservation of matter, which of the following may never occur as a result of a chemical reaction?

Select one:

a. creating of new chemical species
b. reaction of starting materials
c. rearranged to form new substances
d. reduction in total mass

Answer 11

d. reduction in total mass

Question 12

Which is not a meaning of oxidation?

Select one:

a. to gain electrons
b. to lose hydrogen
c. to combine with oxygen
d. to lose electrons

Answer 12

a. to gain electrons

Question 13

For the reaction of HCl and NaOH, which of the following type of chemicals will appear in the net equation?

Select one:

a. weak acid
b. weak base
c. salt
d. water

Answer 13

d. water

Question 14

Which of the following types of chemical reaction classes always involve oxidation?

Select one:

a. Single replacement
b. Double replacement
c. Combination
d. Decomposition

Answer 14

a. Single replacement

Question 15

What is the oxidation number of an uncombined element?

Select one:

a. +1
b. -1
c. 0
d. -2

Answer 15

c. 0

Question 16

Which of the following reactions is correctly balanced?

Select one:

a. N2 + H2–> 2NH3
b. 2H2O + C –> CO + 2H2
c. Zn + 2HCl –> H2 + ZnCl2
d. CO + O2 –> CO2

Answer 16

c. Zn + 2HCl –> H2 + ZnCl2

Question 17

Which set of coefficients balances the equation?

_____ CH4 –> _____ C3H8 + _____H2

Select one:

a. 3,1,1
b. 3,2,1
c. 3,1,2
d. 6,2,2

Answer 17

c. 3,1,2

Question 18

When the equation below is properly balanced, what coefficient is in front of KCl?

KClO3–> KCl + O2

Select one:

a. 1
b. 2
c. 3
d. 4

Answer 18

b. 2

Question 19

Given the equation 2 CO + O2 –> 2CO2, how many grams of CO2 form if 34.0 grams of CO are combined with excess oxygen?

Select one:

a. 53.4
b. 21.6
c. 145
d. 107

Answer 19

a. 53.4

Question 20

Oxygen can be prepared in the lab by heating potassium chlorate in the presence of a catalyst. The reaction is 2KClO3 –> 2KCl + 3O2. How many moles of O2 could be obtained from one mole of KClO3?

Select one:

a. 1.5
b. 3.0
c. 1.0
d. 2.0

Answer 20

a. 1.5

Question 21

In the Haber process, ammonia, NH3 is manufactured from nitrogen, N2, and hydrogen, H2, according to the reaction N2 + 3H2 –> 2NH3 . How many moles of H2 will combine with one mole of N2 in this process?

Select one:

a. 1
b. 2
c. 3
d. 6

Answer 21

c. 3

Question 22

In the Haber process, ammonia, NH3 is manufactured from nitrogen, N2, and hydrogen, H2, according to the reaction N2 + 3H2 –> - Use this equation to answer the Question

According to mole interpretation, how many grams of N2 will react with 3.03 grams of H2?

Select one:

a. 1.00
b. 6.00
c. 14.0
d. 28.0

Answer 22

c. 14.0

Question 23

In the Haber process, ammonia, NH3 is manufactured from nitrogen, N2, and hydrogen, H2, according to the reaction N2 + 3H2 –> 2NH3 - Use this equation to answer this question

According to mole interpretation, how many grams of NH3 could be produced by the complete reaction of 2.80 grams N2 and excess H2?

Select one:

a. 34.0
b. 17.0
c. 3.10
d. 3.40

Answer 23

d. 3.40

Question 24

In the Haber process, ammonia, NH3 is manufactured from nitrogen, N2, and hydrogen, H2, according to the reaction N2 + 3H2 –> 2NH3- Use this equation to answer this question

In the reaction 2H2O –> 2H2 + O2, 2.0 moles of water will produce how many grams of O2?

Select one:

a. 16
b. 32
c. 36
d. 64

Answer 24

b. 32

Question 25

In the Haber process, ammonia, NH3 is manufactured from nitrogen, N2, and hydrogen, H2, according to the reaction N2 +3H2 –> 2NH3- Use this equation to answer this question

In the reaction 2CH4 + O2 ___> 2CO + 4H2, how many molecules of CO will produced by the complete reaction of 1.60 grams of CH4?

Select one:

a. 12.0 X 10^23
b. 3.01 X 10^22
c. 6.02 X 10^22
d. 2.00

Answer 25

c. 6.02 X 10^22