Exam 3 (Chapters 6, 7, and 8)

How many moles of Pb are in 4.71x10^21 Pb atoms?

0.00782

How many moles are there in 17.5 grams of sodium?

0.761

How many atoms are in 1.50 moles of fluorine gas?

1.81 x 10^24

One mole of boron has a mass of ________ g.

10.811

In the reaction given below, if 12 molecules of aluminum oxide are consumed, how many molecules of oxygen gas are produced? 2Al2O3 ---> 4Al + 3O2

18

What are the coefficients for the following reaction when it is properly balanced? ___HCl + ____Mg---> ____MgCl2 + ____H2

2, 1, 1, 1

What are the coefficients for the following reaction when it is properly balanced? ____ HCl+ _____Mg---> _____MgCl2+______H2

2, 1, 1, 1

What are the coefficients for the following reaction when it is properly balanced? ___O2 +___CH4---> ___CO2___H2O

2, 1, 1, 2

What are the coefficients for the following reaction when it is properly balanced? ____O2 + _____CH4----> ____CO2 + _____H2O

2, 1, 1, 2

What are the coefficients for the following reaction when it is properly balanced?___nitrogenmonoxide+ ___carbonmonoxide---> ___nitrogen + ___carbondioxide

2, 2, 1, 2

What are the coefficients for the following reaction when it is properly balanced? ____ Na3PO4 + ____Ba(NO3)2---> ____NaNO3 + ____Ba3 (PO4)2

2, 3, 6, 1

What are the coefficients for the following reaction when it is properly balanced? ___Na3PO4 +___Ba(NO3)2---->___NaNO3___Ba3(PO4)2

2, 3, 6, 1

How many moles of Cu are in 1.48x10^25 Cu atoms?

24.6

In the reaction given below, for every two molecules of aluminum oxide consumed, how many molecules of oxygen are produced? 2Al2O3 ---> 4Al + 3O2

3

How many atoms are in 5.80 moles of He?

3.49 x 10^24

How many moles of iron are contained in 1.75 kg of iron?

31.3

One mole of oxygen gas has a mass of ________ g

32.0

What is the mass in grams of 5.40 moles of lithium?

37.5

What is mass of 0.560 moles of chlorine gas?

39.7

What is the correct value for Avogadro's number?

6.022 x 10^23

For the reaction given below, how many molecules of aluminum will react if 12 molecules of Br2 react and 8 molecules of AlBr3 are produced? 2 Al + 3 Br2 ----> 2AlBr3

8

When the equation, ___O2+ ____C5H12---> ____CO2 + _____H2O, is balanced the coefficient of O2 is

8

When the equation, _____O2+ _____ C5H12----> ____ CO2+ ____ H2O is balanced, the coefficient of O2 is:

8

Considering the following precipitation reaction: Pb(NO3)2(aq) + 2KI(aq)---> PbI2(s) + 2KNO3(aq) Which compound would not form ions in the complete ionic equation? A) PbI2 B) KNO3 C) Pb(NO3)2 D) KI E) All compounds form ions in the complete ionic equation.

A

In writing the chemical equation for a precipitation reaction, what abbreviation of the physical state must appear with one of the products? A) (s) B) (g) C) (l) D) (w) E) none of the above

A

Considering the following precipitation reaction: Pb(NO3)2(aq) + 2KI(aq)---> PbI2(s) + 2KNO3(aq) Which ion(s) would not be present in the net ionic equation? A), 2Pb+2, NO3- B) , K+ 3NO- C) K+, Pb+2 D) ,K+ I- E) All the above ions are in the net ionic equation.

B

If you had an aqueous mixture that contained, Ag+, K+, Pb+2, and cations, how many different , solids could precipitate if a chloride solution was added? A) 1 B) 2 C) 3 D) 4 E) no solids will precipitate

B

You have 10.0 g each of Na, C, Pb, Cu and Ne. Which contains the largest number of moles?

C

In the reaction shown below, which substance is a solid? Cu(s) + H2SO4(aq) --> CuSO4(aq) + H2(g)

Cu

A precipitate is expected to be formed when an aqueous solution of sodium sulfate is added to an aqueous solution of A) iron(III) chloride B) potassium chloride C) magnesium chloride D) barium chloride E) none of the above

D

Considering the following precipitation reaction: Pb(NO3)2(aq) + 2KI(aq)---> PbI2(s) + 2KNO3(aq) Which ion would not be present in the complete ionic equation? A) Pb+2 B) K+ C) NO3- D) I- E) All the above ions are in the complete ionic equation.

E

What type of a reaction occurs when a potassium nitrate solution is mixed with a barium acetate solution? A) precipitation B) acid-base neutralization C) oxidation-reduction D) gas evolution E) no reaction

E

In the reaction shown below, which substances are dissolved in water? Cu(s) + H2SO4(aq) --> CuSO4(aq) + H2(g)

H2SO4 and CuSO4

What are the coefficients for the following reaction when it is properly balanced?___nitricacid + ___sodiumhydroxide ---->___sodiumnitrate + ___water

HNO3, NaOH, NaNO3, H20

What are the coefficients for the following reaction when it is properly balanced?___potassiumiodide+ ___lead(II)acetate---> ___leadIIiodide+ ___potassium acetate A) 2, 1, 1, 1 B) 2, 1, 1, 2 C) 3, 2, 2, 1 D) 1, 1, 2, 2 E) none of the above

KI, Pb(C2H3O2)2, PbI2, KCH3CO2

You have 10.0 g each of Na, C, Pb, Cu and Ne. Which contains the smallest number of moles?

Pb

A redox reaction has occurred __________. A) when a substance reacts with elemental oxygen B) when an alkali metal reacts with an alkaline earth metal C) when one substance transfers electrons or protons to another D) when one substance forms a solid E) when all of the above occur

a

Potassium metal and chlorine gas react in a combination reaction to produce an ionic compound. What is the correct balanced equation for this reaction? a.2 K(s) + Cl2(g) ---> 2 KCl(s) b.K(s) + Cl2(g) ---> KCl(s) c.K(s) + Cl(g) ---> KCl(s) d.K2(s) + Cl2(g) ---> 2 KCl(s) e.K(s) + Cl2(g) ---> KCl2(s)

a

What is the complete ionic equation for the reaction of hydrochloric acid with potassium hydroxide? A) H+ +Cl- +K+ +OH- ---> H2O +K+ +Cl- B) H+ +Cl- +K+ +OH- ---> 2H+ +O2- +K+ +Cl- C) H+ +OH- --->H2O D) 2H+ +2Cl- +K2+ +2OH- --->H2O +K2+ +2Cl- E) none of the above

a

What type of a reaction occurs when a silver nitrate solution is mixed with sodium chloride solution? A) precipitation B) acid-base neutralization C) oxidation-reduction D) gas evolution E) no reaction

a

What type of reaction is the generic equation ? A+B--->AB A) synthesis/combination B) decomposition C) single displacement D) double-displacement E) none of the above

a

When water is heated, bubbles form in the water. Is this evidence of a chemical reaction? Why? A) No, boiling water is a physical change. B) Yes, the formation of a gas is evidence of a chemical reaction. C) No, the formation of gas bubbles is a secondary chemical reaction which is ignored. D) Yes, the formation of a gas is proof a new compound has been made. E) none of the above

a

When water is heated, bubbles form in the water. Is this evidence of a chemical reaction? Why? A) No, boiling water is a physical change. B) Yes, the formation of a gas is evidence of a chemical reaction. C) No, the formation of gas bubbles is a secondary chemical reaction which is ignored. D) Yes, the formation of a gas is proof a new compound has been made. E) none of the above

a

Methane gas (CH4), on complete combustion in air, produces: 1. CO2 2. H2 3. H2O A) 1 and 2 only B) 1 and 3 only C) 2 and 3 only D) All of 1 and 2 only E) None of

b

The Roman numerals in the reaction given represent the coefficients in the balanced chemical equation. What are the values of the coefficients? I NH3 + II O2 III NO + IV H2O I II III IV a.2 5 2 3 b.4 5 4 6 c.2 2 2 3 d.4 4 4 6 e.8 10 8 12

b

What are the coefficients for the following reaction when it is properly balanced?___nitrogenmonoxide+ ___carbonmonoxide---> ___nitrogen+ ___carbondioxide A) 2, 1, 1, 2 B) 2, 2, 1, 2 C) 2, 2, 2, 1 D) 1, 1, 2, 2 E) none of the above

b

What type of a reaction occurs when a sodium hydroxide solution is mixed with an acetic acid solution? A) precipitation B) acid-base neutralization C) oxidation-reduction D) gas evolution E) no reaction

b

What type of reaction is the generic equation ? AB --->A +B A) synthesis/combination B) decomposition C) single displacement D) double-displacement E) none of the above

b

Which of the following statements about balancing reactions is FALSE?A) If there is no coefficient or subscript, a one is implied. B) When coefficients are added the type of compounds is changed in the chemical reaction. C) Subscripts are multiplied by the coefficients to determine the number of atoms in a compound. D) Coefficients are added to compounds to ensure both sides of the reaction have equal numbers of each atom. E) All of the above statements are true.

b

A reaction which forms a solid product is an example of a(n)________. A) oxidation-reduction reaction B) combustion reaction C) precipitation reaction D) gas evolution reaction E) none of the above

c

Before a chemical equation can be written, one must know A) the atomic mass of all the elements involved. B) the molar mass of all the compounds. C) the symbols and formulas of all reactants and products. D) the number of moles of all reactants and products. E) none of the above.

c

Considering the following precipitation reaction: Pb(NO3)2(aq) + 2KI(aq)---> PbI2(s) + 2KNO3(aq) What is the correct complete ionic equation a. Pb+2 +(NO3)2- +2K+ + 2I----> PbI2(s) + 2K+ +2NO3- b. Pb+2 +2NO3- +2K+ +I- ---> PbI2(s) + 2K+ +NO3- c. Pb+2 + 2NO2- + 2K+ +2I- ---> PbI2(s) +2K+ +2NO3- d. Pb+2 +2NO3- + 2K+ +2I- ---> Pb+2 +2I- +2K+ +2NO3- e. none of the above

c

Identify the double displacement reactions among the following: 1. KCl(aq) +AgNO3(aq) ---> AgCl(s) +KNO3(aq) 2. Na2SO4(aq) +BaCl2(aq) --->BaSO4(s) +2NaCl(aq) 3. H2SO4(aq) +2NaOH(aq) --->Na2SO4(aq) 2H2O(l) A) 1 and 2 only B) 1 and 3 only C) 2 and 3 only D) All of 1, 2, and 3 E) None of 1, 2, and 3

c

The Roman numerals in the reaction given represent the coefficients in the balanced chemical equation. What are the values of the coefficients? I Al + II H2SO4 III Al2(SO4)3 + IV H2 I II III IV a.3 1 3 2 b.3 1 1 3 c.2 3 1 3 d.2 3 2 3 e.4 6 1 6

c

The Roman numerals in the reaction given represent the coefficients in the balanced chemical equation. What are the values of the coefficients? I CH3OH + II O2 III CO2 + IV H2O I II III IV a.1 2 1 2 b.1 3 1 2 c.2 3 2 4 d.2 5 2 2 e.4 6 4 8

c

The Roman numerals in the reaction given represent the coefficients in the balanced chemical equation. What are the values of the coefficients? I Fe3O4 + II H2 III Fe + IV H2O I II III IV a.1 1 3 2 b.1 2 3 2 c.1 4 3 4 d.2 8 6 8 e.2 4 6 4

c

The Roman numerals in the reaction given represent the coefficients in the balanced chemical equation. What are the values of the coefficients? I Ni(ClO4)2 + II K2S III KClO4 + IV NiS I II III IV a.2 1 1 2 b.1 2 1 1 c.1 1 2 1 d.1 1 1 2 e.1 2 2 1

c

What type of a reaction occurs when potassium metal reacts with fluorine gas? A) precipitation B) acid-base neutralization C) oxidation-reduction D) gas evolution E) no reaction

c

What type of reaction is the generic equation A+ BC --->AC +B A) synthesis/combination B) decomposition C) single displacement D) double-displacement E) none of the above

c

When the equation, _____N2 + _____H2 ---> ____NH3 is balanced, the coefficient of hydrogen is: A) 1 B) 2 C) 3 D) 4 E) none of the above s

c

When the equation, _____N2+_______H2---> NH3 is balanced, the coefficient of hydrogen is: A) 1 B) 2 C) 3 D) 4 E) none of the above

c

Which is a spectator ion from the following complete ionic equation:Ag+(aq) +NO3-(aq) +K+(aq) +Br-(aq) ---> AgBr(s) +K+(aq) +NO3(aq) A) Ag+B) Br-C) K+ D) AgBr E) none of the above

c

Which of the following everyday substances does not typically contain an acid? A) lemons B) vinegar C) soap D) limes E) all of the above

c

Which of the following statements about redox reactions is FALSE? A) Oxidation is the loss of electrons. B) Reduction is the gain of electrons. C) A reaction can result in either oxidation or reduction, not both. D) A reaction involving elemental oxygen is a redox reaction. E) All of the above statement are true.

c

Which of the following types of compounds will not undergo a gas evolution reaction when acid is added? A) sulfides B) carbonates C) hydroxides D) bisulfites E) none of the above

c

hat is the net ionic equation for the reaction of hydrochloric acid with potassium hydroxide? A) H+ +Cl- +K+ +OH- --->H2O +K+ +Cl- B) HCl +KOH- ---> H2O +KCl C) H+ +OH- ---> H2O D) 2H+ +2Cl- +K2+ +2OH- ---> H2O +K2+ +2Cl- E) none of the above

c

A reaction which forms a gaseous product is an example of a(n)________. A) oxidation-reduction reaction B) combustion reaction C) precipitation reaction D) gas evolution reaction E) none of the above

d

An aqueous solution is: A) any liquid with another compound dissolved in it. B) an ionic compound with water dissolved in it. C) water with a molecular compound dissolved in it. D) water with another compound dissolved in it. E) none of the above

d

An aqueous solution is:A) any liquid with another compound dissolved in it. B) an ionic compound with water dissolved in it. C) water with a molecular compound dissolved in it. D) water with another compound dissolved in it. E) none of the above

d

Considering the following precipitation reaction: Pb(NO3)2(aq) + 2KI(aq)---> PbI2(s) + 2KNO3(aq) What is the correct net ionic equation? A)Pb2+ +I2- ---> PbI2(s) B) 2NO3- +2K+ --->2KNO3 C) Pb2+ +2NO3- +2K+ +2I- ---->PbI2(s) +2K- +2NO3- D) Pb2+ +2I- --->PbI2(s) E) none of the above

d

Considering the following precipitation reaction: Pb(NO3)2(aq) + 2KI(aq)---> PbI2(s) + 2KNO3(aq) Which ion(s) would not be spectator ions? A), Pb+2, NO3- B) K+, I- C) NO3-, Pb+2 D), Pb+2 , I- E) All the above ions are in the net ionic equation.

d

Identify the oxidation-reduction reactions among the following: 1.Zn(s) +Cu2+(aq) ---> Zn2+(aq) +Cu(s) 2.2Na(s) +Cl2(aq) ---> 2NaCl(s) 3. 2Mg(s) +O2(g) ---> 2MgO A) 1 and 2 only B) 1 and 3 only C) 2 and 3 only D) All of 1, 2, and 3 E) None of 1, 2, and 3

d

The Roman numerals in the reaction given represent the coefficients in the balanced chemical equation. What are the values of the coefficients? I KO2 + II H2O III KOH + IV O2 I II III IV a.2 1 2 1 b.2 2 4 3 c.1 1 1 1 d.4 2 4 3 e.8 4 8 6

d

What are the coefficients for the following reaction when it is properly balanced?___nitricacid+___sodiumhydroxide --->___sodiumnitrate+___water A) 2, 1, 1, 1 B) 2, 3, 2, 2 C) 5, 2, 2, 1 D) 1, 1, 1, 1 E) none of the above

d

What is the gas produced when hydrochloric acid is reacted with ammonium carbonate? A) ammonia B) chlorine C) hydrogen D) carbon dioxide E) none of the above

d

What is the molecular equation for the reaction of hydrochloric acid with potassium hydroxide? A) H2Cl +2KOH ---> H2O +2KCl B) 2HCl +K(OH)2 ---> 2H2O +KCl2 C) HCl +KOH ---> H2O +KCl

d

What type of a reaction occurs when a hydrochloric acid solution is mixed with a sodium bicarbonate solution? A) precipitation B) acid-base neutralization C) oxidation-reduction D) gas evolution E) no reaction

d

What type of reaction is the generic equation ?AB +CD ---> AD +CB A) synthesis/combination B) decomposition C) single displacement D) double-displacement E) none of the above

d

When a solution of MgCl2 and one of AgNO3 are mixed, the net ionic equation is A)Mg2+ (aq) +2Cl-(aq) +2Ag+(aq) +2NO3-(aq) ---> Mg2+(aq) +2NO3(aq) +2AgCl(s) B)Mg2+(aq) +2Cl-(aq) +2Ag+(aq) +2NO3-(aq) ---->Mg(NO3)2(aq) +2AgCl(s) C)Mg2+(aq) +2NO3-(aq) ---> Mg(NO3)2(aq) D) Cl-(aq) +Ag+(aq) ---> AgCl(s) E) none of the above

d

Which of the following statements about the mole is FALSE? A) The size of a mole of atoms has a reasonable mass. B) A mole of an element corresponds to one Avogadro number of atoms. C) One mole of an element has a mass equal to its atomic mass expressed in grams. D) One mole of water contains 1/2 mole of oxygen atoms. E) none of the above

d

1) Which of the following is NOT evidence that a chemical reaction has occurred? A) color change B) solid formation C) gas formation D) release of heat E) All of the above are evidence of a chemical reaction.

e

The Roman numerals in the reaction given represent the coefficients in the balanced chemical equation. What are the values of the coefficients? I BaCl2 + II AgNO3 III Ba(NO3)2 + IV AgCl I II III IV a.1 2 2 1 b.1 1 2 2 c.2 1 1 1 d.1 1 1 2 e.1 2 1 2

e

The Roman numerals in the reaction given represent the coefficients in the balanced chemical equation. What are the values of the coefficients? I K2S + II AlCl3 III KCl + IV Al2S3 I II III IV a.3 2 3 2 b.2 3 2 3 c.1 1 2 1 d.3 2 6 2 e.3 2 6 1

e

Which of the following is NOT a sign of a chemical reaction? A) absorbing heat B) emission of heat C) color changeD) solid formationE) All of the above are signs of a chemical reaction.

e

Which of the following is NOT evidence that a chemical reaction has occurred? A) color change B) solid formation C) gas formation D) emission of light E) All of the above are evidence of a chemical reaction.

e

Which of the following statements about writing molecular, complete and net ionic equations is FALSE? A) A molecular equation is a chemical equation showing the complete, neutral formulas for every compound in a reaction. B) A complete ionic equation is a chemical equation showing all of the species as they are actually present in solution. C) A net ionic equation is an equation showing only the species that actually change during the reaction. D) A spectator ion remains unchanged in the reaction and appears on both sides of the equation. E) All of the statements are true.

e

magnesium phosphate; soluble or inso.

inso.

aluminum sulfide; Soluble of insoluble

insol.

All hydroxides are ________except for those of alkali metals, ammonium, and barium.

insoluble

All normal carbonates and phosphates are ________ except for those of alkali metals and ammonium.

insoluble

All sulfides are _______- except for those of alkali metals, alkaline earth metals, and ammonium.

insoluble

PbCl2; soluble or insoluble

insoluble

aluminum sulfate; soluable or insol.

sol.

potassium carbonate; soluable or insol.

solu.

All acetates are

soluble

All chlorides, bromides, and iodides are_______ except for silver, mercury (+1 only), and lead.

soluble

All nitrates are

soluble

All salts of sodium, potassium, and ammonium are _______ except for: sodium antimonate, potassium and ammonium hexachloroplatinate, potassium and ammonium cobaltinitrite

soluble

All sulfates are ______ except for those of alkali earth metals heavier than magnesium, silver and mercury (+1).

soluble