Chemistry Chapter 21 Which of the following statements about the use of sodium

General Chemistry, 11e (Petrucci)

Chapter 21 Chemistry of the Main-Group Elements I: Groups 1, 2, 13, and 14

1) The chemistry of Be is different from that of the other group 2 metals due to the small size of Be2+.

2) A magnesium fire can always be extinguished with carbon dioxide.

3) The atomic radius of calcium is smaller than that of strontium.

4) Strontium is a softer metal than calcium.

5) Strontium hydroxide is classified as “basic.”

6) Strontium hydroxide is more soluble in water than is calcium hydroxide.

7) The first ionization energy of calcium is smaller than that of strontium.

8) Metal oxides generally form an acidic solution in water.

9) In a nonmetal hydroxide the oxygen-hydrogen bond is generally less polar than the nonmetal-oxygen

bond.

10) Hydrogen peroxide may act only as an oxidizing agent.

11) The formula for barium superoxide is BaO2.

12) An amphoteric substance acts as an acid in strongly basic solution and as a base in strongly acidic

solution.

13) Which of the following is INCORRECT?

A reaction typical for an alkali metal (M) is:

A) M2O + H2O → 2 MOH

B) M + X2 → MX2 (X = halogen)

C) 2 M + 2 NH3 → 2 MNH2 + H2

D) 2 M + O2 → M2O2

E) 2 M + H2 → 2 MH

14) The only by-product obtained in the Solvay process is:

A) NH3

B) CO2

C) CaO

D) CaCl2

E) NH4Cl

15) Sodium will most readily form which of the following compounds?

A) Na3As

B) Na3P

C) NaCl

D) Na4P

E) As3Na

16) Which of the following is uncharacteristic of the alkali metals?

A) low ionization energy

B) low electronegativity

C) large negative electrode potential

D) two electrons in the valence shell

E) produce colored flames when heated

17) Which of the following is uncharacteristic of the alkali metals?

A) large electronegativity

B) soft

C) produce visible color in flame test

D) low melting points

E) low ionization energies

18) Which of the following statements about lithium is FALSE?

A) It is used as an alloying agent with aluminum and magnesium.

B) Lithium alloys are high strength and low density.

C) The alloys are important in aerospace and aircraft industries.

D) Lithium is used in batteries because it is difficult to oxidize.

E) An advantage to lithium batteries is light weight.

19) Which of the following statements about the use of sodium is FALSE?

A) Sodium vapor lamps are used outdoors.

B) Sodium is used in reactors because it has a low melting point.

C) Sodium is used in reactors because it has a high boiling point.

D) Sodium is used in reactors because it has a high thermal conductivity.

E) A typical sodium vapor lamp uses several grams of sodium.

20) Choose the INCORRECT statement.

A) Sodium chloride may be produced by electrolysis of sodium metal and chlorine gas.

B) Sodium chloride is one of the most used minerals in the production of chemicals.

C) Sodium chloride is used to preserve meat and fish.

D) Sodium chloride is used to control ice on roads.

E) Sodium chloride is used to regenerate water softeners.

21) Choose the INCORRECT statement.

A) Potassium chloride is used in fertilizers.

B) All alkali metals react alike.

C) Sodium carbonate is called soda ash.

D) Sodium carbonate usually comes from natural sources such as dry lake beds.

E) Sodium carbonate can be made by the Solvay process.

22) Which of the following react with water without the formation of H2 gas as a product?

A) KO2

B) NaH

C) Li

D) Sr

23) Which of the following metals reacts most violently with water?

A) Cs

B) Na

C) Mg

D) Ba

24) Choose the INCORRECT statement.

A) The diagonal relationship is the similarity of properties of the top element of one group to the second

element of the next group.

B) Li – Mg is a diagonal relationship.

C) C – P is a diagonal relationship.

D) Be – Al is a diagonal relationship.

E) B – Si is a diagonal relationship.

25) Choose the INCORRECT statement.

A) Sodium bicarbonate is sodium hydrogen carbonate.

B) O22- occurs in a peroxide.

C) O2– occurs in a superoxide.

D) The hydroxides of alkali metals are amphoteric.

E) Alkali metal hydroxides can be used to make soaps and detergents.

26) Choose the INCORRECT statement.

A) The class “detergents” does not include soaps.

B) Detergents are cleansing agents.

C) Detergents emulsify oils.

D) Detergents usually mean synthetic products.

E) A soap is a salt of a metal hydroxide and a fatty acid.

27) The Solvay process involves a reaction of sodium chloride, ammonia and carbon dioxide in aqueous

solution. Of the various possible products, the one least soluble in water is:

A) ammonium bicarbonate

B) “baking soda” (NaHCO3)

C) “sal ammoniac” (NH4Cl)

D) “table salt” (NaCl)

E) “washing soda” (Na2CO3)

28) Which incorrectly shows the main product of reaction of the indicated alkali metal with excess

oxygen?

A) Li/Li2O

B) Na/Na2O2

C) K/K2O2

D) Rb/RbO2

E) Cs/CsO2

29) Choose the INCORRECT statement about Na2CO3.

A) A by-product from the production of Na2CO3 is CaCl2, which has a useful application in some

localities.

B) It is an important commercial compound used in the glass, soap and paper industries.

C) It is produced by the Solvay process which utilizes NaCl and CaO as the primary raw materials in a

multi-step synthesis.

D) It is mined from large deposits in the western United States.

E) Sodium carbonate can be formed by heating sodium bicarbonate.

30) When sodium and potassium react with excess oxygen, the major products are:

A) Na2O2 and KO2

B) NaO2 and KO2

C) Na2O and KO2

D) Na2O2 and K2O2

E) NaO2 and K2O2

31) Write the general reaction for a group 1 (1A) metal with water.

A) 2 M(s) + 2 H2O(l) → H2O2(aq) + 2 MH(s)

B) 2 M(s) + 2 H2O(l) → 2 MOH(aq) + H2(g)

C) M(s) + H2O(l) → MO(s) + H2(g)

D) 2 M(s) + H2O(l) → M2O(s) + H2(g)

E) 2 M(s) + 2H2O(l) → M(OH)2(s) + H2(g)

32) Lithium differs from other members of the group 1 (1A) elements in which way?

A) It does not react with water under any conditions.

B) It forms a nitride.

C) Its hydroxide is very soluble.

D) It is a rather soft metal.

E) It is a good reducing agent.

33) Finish the following reaction:

Li(s) + O2(g) →

A) 2 Li(s) + O2(g) → Li2O2(s)

B) 2 Li(s) + O2(g) → 2 LiO(s)

C) 4 Li(s) + O2(g) → 2 Li2O(s)

D) Li(s) + O2(g) → LiO2(s)

E) There is no reaction.

34) Finish the following reaction:

Li(s) + N2(g) →

A) 3 Li(s) + N2(g) → Li3N2(s)

B) 4 Li(s) + N2(g) → 2 Li2N(s)

C) 2 Li(s) + N2(g) → 2 LiN(s)

D) 6 Li(s) + N2(g) → 2 Li3N(s)

E) There is no reaction.

35) Finish the following reaction:

SnO2 + NaOH(aq) + H2O(l) →

A) SnO2(s) + 2 NaOH(aq) + 2 H2O(l) → Na2Sn(OH)6(s)

B) SnO2(s) + 2 NaOH(aq) + 2 H2O(l) → Sn(OH)2(s) + 2 NaO(s) + 2 H2O(l)

C) SnO2(s) + 2 NaOH(aq) + 2 H2O(l) → Sn(OH)4(s) + 2 NaO(s) + H2(g)

D) SnO2(s) + 2 NaOH(aq) + 2 H2O(l) → Sn(OH)2(s) + 2 Na(s) + 2 H2O2(aq)

E) There is no reaction.

36) In the production of magnesium metal by the Dow process, the other immediate product of the

electrolysis of the molten magnesium chloride is:

A) H2(g)

B) HCl(g)

C) Cl2(g)

D) MgO(s)

E) Mg(OH)2(s)

37) Choose the INCORRECT statement about magnesium.

A) Magnesium is valued for its light weight.

B) It has a lower density than any other structural metal.

C) Aircraft parts are made from magnesium alloys.

D) It is a good oxidizing agent.

E) It is often used as a sacrificial anode.

38) Choose the INCORRECT statement.

A) Group 2 (2A) compounds are less soluble than Group 1 (1A) compounds.

B) Group 2 (2A) compounds often form hydrates.

C) Hydrates are compounds that have water molecules bonded to them.

D) Group 2 (2A) elements react with halogens to form metal halides.

E) Limestone is CaCl2.

39) Choose the INCORRECT statement.

A) The production of limestone is called calcination.

B) Limestone is mostly calcium carbonate.

C) Stalactites are calcium carbonate formed as icicle-like deposits.

D) Stalagmites form from the floor by deposition of calcium carbonate.

E) Carbonic acid is a diprotic acid.

40) Choose the INCORRECT statement.

A) Gypsum is CaSO4 ∙ 2H2O.

B) Plaster of Paris is calcium sulfate hexahydrate.

C) Quicklime is calcium oxide.

D) Slaked lime is calcium hydroxide.

E) Mortar used in bricklaying is made of slaked lime, sand, and water.

41) Both gypsum and plaster of Paris contain the same compound, but in different stages of hydration.

That compound is:

A) BaSO4

B) BaCO3

C) CaSO4

D) CaCO3

E) KAl(SO4)2

42) Choose the INCORRECT statement about the alkaline earth metals.

A) The heavier Group 2 (2A) metals are nearly as active as the Group 1 (1A) metals.

B) They are the Group 1 (1A) family.

C) Magnesium metal is produced by the Dow process.

D) Salts of Sr and Ba provide vivid colors for pyrotechnic displays.

E) The source of magnesium is seawater and natural brines.

43) In the stepwise preparation of pure calcium carbonate from limestone, the step referred to as

calcination involves:

A) thermal decomposition of calcium carbonate to calcium oxide

B) addition of water to calcium oxide to form calcium hydroxide

C) bubbling carbon dioxide through aqueous calcium hydroxide

D) heating calcium oxide with carbon to form calcium metal

E) melting of calcium oxide

44) In seawater, Mg2+ is about 1350 mg Mg2+/L. How many grams of magnesium are in a pool that is 25

ft by 12 ft by 6 ft? (1 ft = 12 inches and 1 inch = 2.54 cm)

A) 4.78 × 102 g

B) 74.1 g

C) 6.88 × 104 g

D) 6.88 × 107 g

E) 1.64 × 103 g

45) Which hydroxide is significantly more soluble in 0.10 M NaOH than in pure water?

A) Mg(OH)2

B) Be(OH)2

C) NaOH

D) Ca(OH)2

E) CsOH

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46) Which of the following metal hydroxides has the lowest solubility?

A) NaOH

B) LiOH

C) Mg(OH)2

D) Ba(OH)2

E) Sr(OH)2

47) Which of the following is used as a water softener?

A) lithium carbonate

B) sodium nitrate

C) sodium carbonate

D) potassium chloride

E) hydrochloric acid

48) The difference between temporary hard water and permanent hard water is that only the former

contains a significant concentration of:

A) Ca2+

B) CO32-

C) HCO3–

D) Mg2+

E) OH–

49) Choose the INCORRECT statement.

A) Temporary hard water contains the bicarbonate ion.

B) Permanent hard water also contains anions other than bicarbonate.

C) Ion exchange is accomplished by mixing chemicals in the water to precipitate hard water ions.

D) Deionized water is water with ions removed by ion exchange.

E) Boiler scale is a mixed precipitate of CaCO3, MgCO3, and rust.

50) Which of the following methods are unable to make water soft?

A) add CaO

B) add Na2CO3

C) boil

D) pass through ion exchange

E) pass through charcoal

51) Water treatment using a cation-exchange resin in the H+ form, followed by an anion-exchange resin in

the OH– form, unlike the processes using typical zeolites or synthetic resins regenerated by sodium

chloride, can produce:

A) brine water

B) deionized water

C) distilled water

D) hard water

E) soft water

52) In diborane, B2H6, the hybridization of each boron is:

A) sp3

B) sp2

C) sp3d

D) sp

E) sp3d2

53) Which of the following is a weak acid?

A) B(OH)3

B) HI

C) B(OH)4–

D) B2(O2)2(OH)42-

54) Choose the INCORRECT statement.

A) The thermite reaction is: Fe2O3(s) + 2 Al(s) → Al2O3(s) + 2 Fe(l).

B) Aluminum’s chief ore is bauxite.

C) Al2O3 is an amphoteric oxide.

D) Cryolite is Na3AlF6.

E) Alumina is Al(OH)3.

55) Choose the INCORRECT statement.

A) A dimer is a molecule comprised of two like units.

B) Adduct formation results in an ionic bond.

C) Noncrystalline aluminum oxide is referred to as alumina.

D) Crystalline aluminum oxide is called corundum.

E) H– can be thought of as a pseudohalide.

56) Choose the INCORRECT statement about the inert-pair effect.

A) It explains why gallium tends to have the +3 oxidation state but thallium is most often in the +1 state.

B) It can be explained that the bond energies and lattice energies associated with the atoms and ions at the

bottom of the groups are not sufficiently large to off-set the ionization energies of the ns2 electron.

C) The effect is manifested by ions not losing the outermost pair of electrons.

D) Of the group 14 (4A) metals, only tin exhibits the inert-pair effect.

E) For any group, the inert pair effect is more prominent as the period number increases.

57) Which of the following is an indication that aluminum is a strong reducing agent?

A) 2 Al(s) + 6 H+(aq) → 2 Al3+(aq) + 3 H2(g)

B) 2 Al(s) + Fe2O3(s) → Al2O3(s) + 2 Fe(l)

C) 2 Al(s) + 3/2 O2(g) → Al2O3(s)

D) 2 Al(s) + 2 OH– + 6 H2O(l) → 2 [Al(OH)4]–(aq) + 3 H2(g)

E) All of these reactions indicate Al is a strong reducing agent.

58) Which of the following compounds is invoked to demonstrate the inert-pair effect?

A) Al(OH)3

B) GaAs

C) InAs

D) Tl2O

E) Al2O3

59) Which oxidation state is uncommon for a given element?

A) Al/1+

B) Ga/3+

C) Al/3+

D) In/3+

E) In/1+

60) Which of the following statements describes an uncommon use of an element?

A) Aluminum is used in light-weight alloys.

B) Gallium is used in the thermite reaction.

C) Gallium is used in the electronics industry.

D) Indium is used to make low-melting alloys.

E) A possible use for thallium is in high-temperature superconductors.

61) Which of the following metals has been used commercially in certain drain cleaners, along with solid

sodium hydroxide, for the purpose of generating hydrogen gas by reaction with hydroxide ion after

contact with water?

A) Al

B) Ba

C) Cu

D) Fe

E) Ge

62) For which of the following elements would be wrong to call the oxide “amphoteric”?

A) Tl

B) Al

C) Be

D) Ga

63) Tl is different from Al, Ga, and In in that:

A) Tl has a much different electronegativity

B) Tl has a much different first ionization energy

C) Tl commonly forms compounds with +1 oxidation state

D) Tl forms metal hydroxides that are amphoteric

E) Tl commonly forms compounds with +3 oxidation state

64) In the production of the metal by an electrolysis process, which of the following is the most costly in

terms of amount of electricity required per ton of metal produced from its salt?

A) Na

B) Mg

C) Cu

D) Ba

E) Al

65) One of the most important commercial processes for the semiconductor industry in recent years has

been the gas phase reaction between arsine and trimethylgallium to form the solid product:

A) trimethylarsine

B) methyl hydride

C) gallium hydride

D) gallium arsenide

E) superconductine

66) Pick the nonmetal in Group 13 (3A).

A) Al

B) Ga

C) In

D) B

E) Tl