Chem ch. 5

What will be the sum of the oxidation numbers of all the atoms in the polyatomic ion HPO42−? a. 0 b. −2 c. −1 d. +1

b. −2

Which of the following types of chemical reaction classes always involve oxidation? a. single replacement b. double replacement c. combination d. decomposition

a. single replacement

What is the sum of the oxidation numbers of all the atoms in the compound formula K2CO3? a. −2 b. 0 c. −1 d. +1

b. 0

When the equation below is properly balanced, what coefficient is in front of KCl? KClO3 → KCl + O2 a. 1 b. 2 c. 3 d. 4

b. 2

In the reaction 2H2O → 2H2 + O2, 2.0 mol water will produce how many grams of O2? a. 16 b. 32 c. 36 d. 64

b. 32

What is the oxidation number of an uncombined element? a. +1 b. −1 c. 0 d. −2

c. 0

If 5 grams of CO and 5 grams of O2 are combined according to the reaction, which is the limiting reagent? 2CO + O2 → 2CO2 a. CO2 b. O2 c. CO d. CO and O2

c. CO

Which ions in the following reaction would be classified as spectator ions? Zn + 2H+ + 2Cl → Zn2+ + 2Cl− + H2 a. Zn2+ b. H+ c. Cl− d. More than one response is correct.

c. Cl−

What is the oxidation number of Cl in HClO3? a. +2 b. +3 c. +4 d. +5

d. +5

Suppose 2.43 g of magnesium is reacted with 3.20 g of oxygen: 2Mg + O2 → 2MgO. How many grams of MgO will be produced? a. 5.63 b. 1.27 c. 8.06 d. 4.03

d. 4.03

Which of the following is a double replacement reaction? a. CuO + H2 → Cu + H2O b. HBr + KOH → H2O + KBr c. SO2 + H2O → H2SO3 d. 2HI → I2 + H2

b. HBr + KOH → H2O + KBr

What substance is reduced in the following reaction? 4HCl + MnO2 → Cl2 + 2H2O + MnCl2 a. Cl in HCl b. Mn in MnO2 c. H in HCl d. O in MnO2

b. Mn in MnO2

In the equation for an endothermic reaction, the word "heat" appears a. on the right side. b. on the left side. c. on both sides. d. on neither side.

b. on the left side.

What is the oxidation number of Mn in KMnO4? a. +9 b. +5 c. +7 d. +4

c. +7

How many grams of N2 are required to completely react with 3.03 grams of H2 for the following balanced chemical equation? N2 + 3H2 → 2NH3 a. 1.00 b. 6.00 c. 14.0 d. 28.0

c. 14.0

Which of the following is a decomposition reaction? a. SO2 + O2 → 2SO3 b. 2C2H2 + 5O2 → 4CO2 + 2H2O c. 2H2O2 → 2H2O + O2 d. AgNO3 + NaCl → AgCl + NaNO3

c. 2H2O2 → 2H2O + O2

Propane, C3H8, burns to produce carbon dioxide and water by the equation below. What is the coefficient in front of the carbon dioxide in the balanced equation? C3H8 + O2 → CO2 + H2O a. 1 b. 2 c. 3 d. 6

c. 3

Which set of coefficients balances the equation? ____ CH4 → ____C3H8 + ____ H2 a. 3,1,1 b. 3,2,1 c. 3,1,2 d. 6,2,2

c. 3,1,2

What are coefficients needed to balance the following reaction? 2 CH4 + ____ O2 → ____ CO2 + ____ H2O a. 8,2,4 b. 4,1,2 c. 4,2,4 d. none of these

c. 4,2,4

Which of the following contains the metal with the highest oxidation number? a. CaCl2 b. NaCl c. FeCl3 d. CuCl2

c. FeCl3

Consider the reactants and propose the right side of the equation. Mg + H2SO4 → _______ a. no reaction b. MgHSO4 c. MgSO4 + H2 d. MgH2 + SO4

c. MgSO4 + H2

A REDOX reaction can also be a(n) a. combination reaction. b. single replacement reaction. c. decomposition reaction. d. More than one response is correct.

d. More than one response is correct.

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

a. 1.5

When the following equation is balanced, how many oxygen atoms are present on the reactant side of the equation? C2H6 + O2 → CO2 + H2O a. 14 b. 7 c. 3 d. 20

a. 14

Given the equation 2CO + O2 → 2CO2, how many grams of CO2 form if 34.0 grams of CO are combined with excess oxygen? a. 53.4 b. 21.6 c. 145 d. 107

a. 53.4

What substance is oxidized in the following reaction? 4HCl + MnO2 → Cl2 + 2H2O + MnCl2 a. Cl in HCl b. Mn in MnO2 c. H in HCl d. O in MnO2

a. Cl in HCl

Which of the following is a single replacement reaction? a. CuO + H2 → Cu + H2O b. HBr + KOH → H2O + KBr c. SO2 + H2O → H2SO3 d. 2HI → I2 + H2

a. CuO + H2 → Cu + H2O

What is the reducing agent in the following reaction? 4HCl + MnO2 → Cl2 + 2H2O + MnCl2 a. HCl b. Cl2 c. MnO2 d. MnCl2

a. HCl

Which of the following is an oxidizing agent? a. O2 b. H2 c. H2O d. HCl

a. O2

Which of the following is a combination reaction? a. SO2 + O2 → 2SO3 b. 2C2H2 + 5O2 → 4CO2 + 2H2O c. 2H2O2 → 2H2O + O2 d. AgNO3 + NaCl → AgCl + NaNO3

a. SO2 + O2 → 2SO3

Single replacement reactions are always a. redox reactions. b. nonredox reactions. c. combination reactions. d. decomposition reactions.

a. redox reactions.

Which is not a meaning of oxidation? a. to gain electrons b. to lose hydrogen c. to combine with oxygen d. to lose electrons

a. to gain electrons

Which of the following phrases can be used to describe the process of reduction? a. to gain oxygen b. to combine with hydrogen c. to gain electrons d. to decrease in oxidation number

a. to gain oxygen

Which of the following reactions is correctly balanced? a. N2 + H → 2NH3 b. 2H2O + C → CO + 2H2 c. Zn + 2HCl → H2 + ZnCl2 d. CO + O2 → CO2

c. Zn + 2HCl → H2 + ZnCl2

The reaction below would be considered _____ . CaCO3 + heat → CaO + CO2 a. an endothermic combination. b. an exothermic combination. c. an endothermic decomposition. d. an exothermic decomposition.

c. an endothermic

Which species would be considered a spectator ion based on the following equation? Ba2+ + 2NO3− + 2Na+ + SO42+ → BaSO4(s) + 2NO3− + 2Na+ a. Ba2+ b. SO42+ c. BaSO4 d. 2NO3−

d. 2NO3−

Consider the reactants in the partial equation given. Which choice is a product? H3PO4 + Sr(OH)2 → ____ a. no reaction b. SrH3PO5 c. SrH5PO6 d. Sr3(PO4)2

d. Sr3(PO4)2

Automotive car batteries rely on the reaction shown below. Identify the spectator ion(s). PbO2(s) + 4 H+(aq) + 2 SO42-(aq) + Pb(s) → 2 PbSO4(s) + 2 H2O(l) a. SO42- b. H+ c. H+ and SO42- d. There are no spectator ions.

d. There are no spectator ions.

Which of the following statements is not true about the reaction? 2 CH4 + 3 O2 → 2 CO2 + 4 H2O a. Water is a reactant. b. Methane and carbon dioxide are products. c. Methane is a product. d. Water and carbon dioxide are products.

d. Water and carbon dioxide are products.

For the reaction of HCl and NaOH, which of the following type of chemicals will appear in the net equation? a. weak acid b. weak base c. salt d. water

d. water