Deck 20: Chemistry of the Metals

Question 1

Write a balanced chemical equation for the chemical reduction of iron(III)oxide that occurs in a blast furnace.

A) Fe₂O₃(s)+ 3CO(g)→ 2Fe(s)+ 3CO₂(g)
B) Fe₂O₃(s)+ 3CO₂(g)→ 2Fe(s)+ 3CO(g)
C) Fe₂O₃(s)+ 3C(g)→ 2Fe(s)+ 3CO(g)
D) FeO(s)+ CO₂(g)→ FeCO₃(s)
E) FeO(s)+ CO(g)→ Fe(s)+ CO₂(g)

Answer 1

Fe₂O₃(s)+ 3CO(g)→ 2Fe(s)+ 3CO₂(g)

Question 2

Aluminum is obtained by

A) the electrolysis of cryolite,Na₃AlF₆.
B) reduction by a strong inorganic reducing agent,such as thiosulfate ion,S₂O₃²⁻.
C) the reduction of Al₂O₃ by carbon monoxide in a blast furnace.
D) chemical decomposition of Al₂O₃ at temperatures greater than 2000°C.
E) electrolysis of a molten mixture of bauxite ore and cryolite,Na₃AlF₆.

Answer 2

electrolysis of a molten mixture of bauxite ore and cryolite,Na₃AlF₆.

Question 3

Both sodium metal and chlorine gas are created by the electrolysis of molten sodium chloride.If 1.00 × 10² amperes of current is passed through the cathode for 8.00 hr,what mass of Cl₂ will be formed? (F = 96480 C/mol e−).

A) 0.588 g
B) 1.18 g
C) 17.6 g
D) 1.06 × 10³ g
E) 2.12 × 10² g

Answer 3

1.06 × 10³ g

Question 4

Aluminum is produced by electrolysis of a mixture of bauxite ore (Al₂O₃)and cryolite (Na₃AlF₆).The purpose of the cryolite is to

A) increase the current.
B) decrease the potential at which aluminum is reduced.
C) convert oxide ion into water
D) lower the melting point.
E) decrease the pH of the molten solution.

Question 5

Write a balanced equation for the reduction of Co₂O₃ by carbon monoxide.

A) Co₂O₃(s)+ CO(g)→ 2Co(s)+ CO₄(g)
B) 2Co₂O₃(s)+ 2CO(g)→ 2Co₂CO₃(s)+O₂(g)
C) Co₂O₃(s)+ CO(g)→ Co(s)+ CO₂(g)
D) Co₂O₃(s)+ CO(g)→ Co(s)+ C(g)+ 2O₂(g)
E) Co₂O₃(s)+ 3CO(g)→ 2Co(s)+ 3CO₂(g)

Question 6

Iron that is made in a blast furnace is called pig iron.The pig iron is converted into steel by reducing its carbon content from roughly 4% to under 2% by

A) reduction of the carbon with hydrogen gas.
B) the addition of calcium oxide to form slag.
C) vacuum filtration.
D) electrolysis.
E) reaction with oxygen to form CO₂(g).

Question 7

Who worked out the process for obtaining aluminum from bauxite ore?

A) Michael Faraday
B) Enrico Fermi
C) Charles Hall
D) Linus Pauling
E) Alfred Werner

Question 8

The main group metals in Group 1 are referred to as the

A) alkali metals.
B) alkaline earth metals.
C) highly reactive metals.
D) transition metals.
E) basic metals.

Question 9

The main group metals in Group 2 are referred to as the

A) alkali metals.
B) alkaline earth metals.
C) less reactive metals.
D) divalent metals.
E) basic metals.

Question 10

Write a balanced chemical equation for the reaction of HgS with O₂.

A) HgS(s)+ O₂(g)→ HgO₂(s)+ S(s)
B) HgS(s)+ O₂(g)→ Hg(l)+ SO₂(g)
C) HgS(s)+ O₂(g)→ HgSO₂(s)
D) HgS(s)+ 2O₂(g)→ HgSO₄(s)
E) 2HgS(s)+ O₂(g)→ HgO(s)+ 2S(s)

Question 11

Copper can be obtained from copper sulfide by heating in the presence of oxygen.This process is called

A) roasting.
B) oxidation.
C) smelting.
D) steaming.
E) alloying.

Question 12

The roasting of Cu₂S(s)produces Cu(s)and SO₂(g).What mass of sulfur dioxide is produced by the roasting of 1.00 × 10³ kg Cu₂S(s)? Cu₂S(s)+ O₂(g)→ 2Cu(s)+ SO₂(g)

A) 201
B) 402 kg
C) 798 kg
D) 804 kg
E) 2.48 × 10³ kg

Question 13

At temperatures greater than 800°C,limestone decomposes according to which balanced chemical equation?

A) CaO(s)→ Ca(s)+ O(g)
B) 2CaO(s)→ 2Ca(s)+ O₂(g)
C) CaCO₃(s)→ CaO(s)+ CO₂(g)
D) CaCO₃(s)→ CaO₂(s)+ CO(g)
E) CaCO₂(g)→ Ca(s)+ CO₂(g)

Question 14

Separation of gold from ore is currently accomplished by using which ligand to make a soluble coordination compound from Au⁺¹?

A) Chloride ion
B) Cyanide ion
C) Ammonia
D) Perchlorate ion
E) Ethylenediamine

Question 15

The iron produced in a blast furnace contains significant impurities of carbon,silicon,manganese,and phosphorus.These impurities are removed in a ________.

A) basic oxygen furnace
B) distillation column
C) mass spectrometer
D) electrolytic cell
E) centrifuge

Question 16

What is a useful by-product of the production of sodium metal?

A) Hydrogen
B) Magnesium
C) Chlorine
D) Helium
E) Calcium

Question 17

All of the following metals may be found in nature as free elements EXCEPT ____.

A) Ir
B) Au
C) Pt
D) Ti
E) Rh

Question 18

Slag is a glassy material that forms when calcium oxide reacts with impurities (mostly silicon dioxide)in a blast furnace.Write the balanced chemical equation for the reaction.

A) CaCO₃(s)+ Si(s)→ CaSiO₃(l)
B) CaCO₃(s)+ SiO₂(s)→ CaSiO₅(l)
C) CaO(s)+ SiO₂(s)→ CaSiO(l)+ O₂(g)
D) CaO(s)+ SiO₂(s)→ CaSiO₃(l)
E) CaO(s)+ SiO(s)→ CaCO₂(l)

Question 19

What is the most common chemical reducing agent in metallurgical processes?

A) Thiosulfate ion,S₂O₃²⁻
B) Oxygen,O₂
C) Sodium metal
D) Carbon;in the form of carbon monoxide
E) Carbon;in the form of carbon dioxide

Question 20

Write a balanced equation for the reduction of manganese(IV)oxide ore by carbon monoxide.

A) MnO(s)+ CO(g)→ Mn(s)+ CO₂(g)
B) MnO(s)+ 2CO(g)→ Mn(s)+ 2CO₂(g)
C) Mn₂O(s)+ CO(g)→ Mn(s)+ CO₂(g)
D) MnO₂(s)+ 2CO(g)→ Mn(s)+ 2CO₂(g)
E) MnO₂(s)+ 2CO(g)→ Mn(s)+ 2C(s)+ O₂(g)

Question 21

Historically,miners separated gold by taking advantage of its

A) high density.
B) low melting point.
C) high solubility in water.
D) radioactivity.
E) amphoteric nature.

Question 22

Which of the following metals will react most violently with water?

A) Li
B) Mg
C) K
D) Ca
E) Cr

Question 23

Write a balanced equation for the reaction of barium and nitrogen gas.

A) Ba(s)+ N₂(g)→ BaN₂(s)
B) 2Ba(s)+ N₂(g)→ 2BaN(s)
C) 2Ba(s)+ N₂(g)→ 2BaN(s)..
D) 3Ba(s)+ N₂(g)→ Ba₃N₂(s)
E) 4Ba(s)+ 3N₂(g)→ 2Ba₂N₃(s)

Question 24

One product of the reaction of sodium and water is sodium hydroxide.What mass of sodium is needed to make 2.0 L of 0.075 M NaOH(aq)?

A) 0.26 g
B) 3.4 g
C) 6.0 g
D) 6.8 g
E) 12 g

Question 25

Write a balanced equation for the oxidation of gold by aqua regia.

A) Au(s)+ 4H⁺(aq)+ 4Cl−(aq)+ NO₃−(aq)→ AuCl₄−(aq)+ NO(g)+ 2H₂O(l)
B) Au(s)+ 4H⁺(aq)+ NO₃−(aq)→ Au³⁺(aq)+ NO(g)+ 4H₂O(l)
C) 2Au(s)+ 6H₂O(l)→ 2Au(OH)₃(s)+ 3H₂(g)
D) 2Au(s)+ 6H⁺(aq)+ 6NO₃−(aq)→ 2Au³⁺(aq)+ NO₃−(aq)+ 3H₂(g)
E) 4Au(s)+ 8CN−(aq)+ O₂(g)+ 2H₂O(l)→ 4Au(CN)₂−(aq)+ 4OH−(aq)

Question 26

What is the percent composition of chalcopyrite,CuFeS₂?

A) 25.0% Cu,25.0% Fe,50.0% S
B) 33.3% Cu,33.3% Fe,33.3% S
C) 34.6% Cu,30.4% Fe,35.0% S
D) 41.2% Cu,17.3% Fe,41.5% S
E) 42.0% Cu,36.9% Fe,21.1% S

Question 27

Write a balanced equation for the reaction of magnesium and nitrogen that occurs upon heating.

A) Mg(s)+ N₂(g)→ MgN₂(s)
B) 2Mg(s)+ N₂(g)→ 2MgN(s)
C) 4Mg(s)+ N₂(g)→ 2Mg₂N(s)
D) 4Mg(s)+ 3N₂(g)→ 2Mg₂N₃(s)
E) 3Mg(s)+ N₂(g)→ Mg₃N₂(s)

Question 28

Write a balanced equation for the oxidation of copper metal by nitric acid.

A) Cu(s)+ 6H⁺(aq)+ NO₃−(aq)→ Cu²⁺(aq)+ NH₃(aq)+ 3H₂O(l)
B) Cu(s)+ 12H⁺(aq)+ 2NO₃−(aq)→ Cu²⁺(aq)+ N₂(g)+ 6H₂O(l)
C) 3Cu(s)+ 8H⁺(aq)+ 2NO₃−(aq)→ 3Cu²⁺(aq)+ 2NO(g)+ 4H₂O(l)
D) 4Cu(s)+ 6H⁺(aq)+ NO₃−(aq)→ 4Cu²⁺(aq)+ NH₃(aq)+ 3H₂O(l)
E) 5Cu(s)+ 12H⁺(aq)+ 2NO₃−(aq)→ 5Cu²⁺(aq)+ N₂(g)+ 6H₂O(l)

Question 29

Potassium superoxide is used in self-contained breathing devices.Its function is to

A) remove nitrogen from exhaled air.
B) absorb smoke or other hazardous vapors.
C) generate oxygen only.
D) remove exhaled carbon dioxide only.
E) both generate oxygen and remove exhaled carbon dioxide.

Question 30

Even in basic solution,MnO₄− can oxidize water.One product is manganese(IV)oxide.Write a balanced chemical equation for the reaction.

A) MnO₄−(aq)+ H₂O(l)→ MnO₂(s)+ H₂(g)+ OH−(aq)
B) MnO₄−(aq)+ 6H₂O(l)→ MnO₂(s)+ 2H₂(g)+ 8OH−(aq)
C) 2MnO₄−(aq)+ 2H₂O(l)→ 2Mn²⁺(aq)+ 3O₂(g)+ 4OH−(aq)
D) 4MnO₄−(aq)+ 2H₂O(l)→ 4MnO₂(s)+ 3O₂(g)+ 4OH−(aq)
E) 4MnO₄−(aq)+ H₂O(l)→ 4MnO(s)+ O₂(g)+ 2OH−(aq)

Question 31

Given the half-reactions and $\mathrm{E}_{\mathrm{red}}^{\circ}$ values below,determine which species is the best reducing agent.
$\begin{array}{ll}\mathrm{MnO}_{4}-(a q)+8 \mathrm{H}^{+}(a q)+5 e^{-} \rightarrow \mathrm{Mn}^{2+}(a q)+4 \mathrm{H}_{2} \mathrm{O}(l) & \mathrm{E}_{\mathrm{red}=+1.512 \mathrm{~V}}^{\circ} \\4 \mathrm{H}^{+}(a q)+\mathrm{NO}_{3}-(a q)+3 e^{-} \rightarrow \mathrm{NO}(g)+2 \mathrm{H}_{2} \mathrm{O}(l) & \mathrm{E}_{\mathrm{red}=+0.964 \mathrm{~V}}^{\circ} \\\mathrm{Fe}^{3+}(a q)+e-\rightarrow \mathrm{Fe}^{2+}(s) & \mathrm{E}_{\mathrm{red}}^{\circ}=+0.771 \mathrm{~V} \\2 \mathrm{H}^{+}(a q)+2 e^{-} \rightarrow \mathrm{H}_{2}(g) & \mathrm{E}_{\text {red }}^{\circ}=0.000 \mathrm{~V}\end{array}$

A) H⁺
B) H₂
C) Fe²⁺
D) NO₃?
E) MnO₄?

Question 32

Write the balanced half-reaction for the reduction of permanganate ion to Mn²⁺ in an acidic solution.

A) MnO₄−(aq)+ 8H⁺(aq)→ Mn²⁺(aq)+ 4H₂O(l)
B) MnO₄−(aq)+ 5e− → Mn²⁺(aq)+ 2O₂(g)
C) MnO₄−(aq)+ 4H⁺(aq)+ 3e− → Mn²⁺(aq)+ 4OH−(aq)
D) MnO₄−(aq)+ 4H⁺(aq)+ 5e− → Mn²⁺(aq)+ 4OH−(aq)
E) MnO₄−(aq)+ 8H⁺(aq)+ 5e− → Mn²⁺(aq)+ 4H₂O(l)

Question 33

Write a balanced equation for the reaction of Na and O₂ to form sodium peroxide.

A) 4Na(s)+ O₂(g)→ 2Na₂O(s)
B) Na(s)+ O₂(g)→ NaO₂(s)
C) 2Na(s)+ O₂(g)→ Na₂O₂(s)
D) 2Na(s)+ O₂(g)→ 2NaO(s)
E) 4Na(s)+ 3O₂(g)→ 2Na₂O₃(s)

Question 34

Write a balanced equation for the reaction of calcium hydride with water.

A) CaH₂(s)+ H₂O(l)→ CaOH₂(s)+ H₂(g)
B) CaH₂(s)+ H₂O(l)→ CaO(s)+ 2H₂(g)
C) CaH₂(s)+ H₂O(l)→ Ca(s)+ 2H₂(g)+ H₂O(l)
D) CaH₂(s)+ 2H₂O(l)→ Ca(s)+ 3H₂(g)+ O₂(l)
E) CaH₂(s)+ 2H₂O(l)→ Ca²⁺(aq)+ 2OH−(aq)+ 2H₂(g)

Question 35

In an aqueous solution,Cu⁺ undergoes a reaction to form Cu(s)and Cu²⁺.This reaction is an example of

A) reduction.
B) oxidation.
C) disproportionation.
D) precipitation.
E) amphoterism.

Question 36

The principal product of the reaction of potassium and oxygen is not K₂O.The product is named ____ and has the formula ____.

A) dipotassium trioxide,K₂O₃
B) potassium monoxide,KO
C) potassium superoxide,KO₂
D) potassium peroxide,K₂O₂
E) potassium trioxide,KO₃

Question 37

Write a balanced chemical equation for the reaction of potassium and water.

A) K(s)+ H₂O(l)→ KO(s)+ H₂(g)
B) 2K(s)+ 2H₂O(l)→ 2KOH(aq)+ H₂(g)
C) 2K(s)+ 2H₂O(l)→ K₂O₂(s)+ 2H₂(g)
D) 2K(s)+ H₂O(l)→ K₂O(s)+ H₂(g)
E) 4K(s)+ 2H₂O(l)→ 4KH(s)+ O₂(g)

Question 38

Strontium oxide reacts with water.Write a balanced equation for this reaction.

A) SrO(s)+ H₂O(l)→ Sr²⁺(aq)+ O²⁻(aq)+ H₂O(l)
B) SrO(s)+ H₂O(l)→ Sr²⁺(aq)+ 2OH−(aq)
C) SrO(s)+ H₂O(l)→ SrH₂(aq)+ O₂(g)
D) SrO(s)+ H₂O(l)→ Sr²⁺(aq)+ 2H−(aq)+ O₂(g)
E) SrO(s)+ H₂O(l)→ Sr(s)+ H₂O₂(aq)

Question 39

Write a balanced equation for the reaction of sodium and bromine.

A) Na(s)+ Br−(l)→ NaBr(s)
B) Na(s)+ Br(l)→ NaBr(s)+ Br−(aq)
C) Na(s)+ Br₂(l)→ NaBr₂(s)
D) 2Na(s)+ Br₂(l)→ 2NaBr(s)
E) 4Na(s))+ Br₂(l)→ 2Na₂Br(s)

Question 40

Given the half-reactions and $\mathrm{E}_{\mathrm{red}}^{\circ}$ values in the table below, determine which species is the best oxidizing agent.
$\begin{array}{ll}\mathrm{MnO}_{4}-(a q)+8 \mathrm{H}^{+}(a q)+5 e^{-} \rightarrow \mathrm{Mn}^{2+}(a q)+4 \mathrm{H}_{2} \mathrm{O}(l) & \mathrm{E}_{\mathrm{red}=+1.512 \mathrm{~V}}^{\circ} \\4 \mathrm{H}^{+}(a q)+\mathrm{NO}_{3}-(a q)+3 e^{-} \rightarrow \mathrm{NO}(g)+2 \mathrm{H}_{2} \mathrm{O}(l) & \mathrm{E}_{\mathrm{red}=+0.964 \mathrm{~V}}^{\circ} \\\mathrm{Fe}^{3+}(a q)+e-\rightarrow \mathrm{Fe}^{2+}(s) & \mathrm{E}_{\mathrm{red}}^{\circ}=+0.771 \mathrm{~V} \\2 \mathrm{H}^{+}(a q)+2 e^{-} \rightarrow \mathrm{H}_{2}(g) & \mathrm{E}_{\text {red }}^{\circ}=0.000 \mathrm{~V}\end{array}$

A) H⁺
B) Fe²⁺
C) Fe³⁺
D) NO₃?
E) MnO₄?

Question 41

Ammonium dichromate, (NH₄)₂Cr₂O₇ decomposes in a reaction that resembles the eruption of a volcano.Write a balanced chemical equation for the reaction.

A) (NH₄)₂Cr₂O₇(s)→ N₂(g)+ 4H₂O(g)+ Cr₂O₃(s)
B) (NH₄)₂Cr₂O₇(s)→ 2NH₃(g)+ H₂Cr₂O₇(s)
C) (NH₄)₂Cr₂O₇(s)→ 2NH₃(g)+ 4H₂O(g)+ 2CrO₃
D) (NH₄)₂Cr₂O₇(s)→ 2NH₄⁺(g)+ Cr₂O₇²⁻(g)
E) (NH₄)₂Cr₂O₇(s)→ 2NH₃(g)+ 3H₂(g)+ H₂O(g)+ 2CrO₃(s)

Question 42

Potassium superoxide is used to generate oxygen in confined places,such as submarines and spacecraft. 4KO₂(s)+ 2CO₂(g)→ K₂CO₃(s)+ 3O₂(g)
What mass of oxygen will be produced for each 1.0 g KO₂ consumed?

A) 0.23 g
B) 0.34 g
C) 0.45 g
D) 0.60 g
E) 1.0 g

Question 43

Which of the following cations is not essential to human nutrition?

A) Hg²⁺
B) Zn²⁺
C) K⁺
D) Ca²⁺
E) Fe²⁺

Question 44

Which of the following cations has the highest concentration in the human body?

A) Na⁺
B) Zn²⁺
C) K⁺
D) Ca²⁺
E) Fe²⁺

Question 45

What group of elements tend to form colored salts?

A) Group 1 metals
B) Group 2 metals
C) Transition metals
D) All of the above
E) None of the above

Question 46

Which metal cation is a component of over 70 enzymes?

A) Al³⁺
B) Ca²⁺
C) Co³⁺
D) Fe²⁺
E) Zn²⁺

Question 47

Sodium azide is used in air bags for automobiles.The gas produced from the decomposition of sodium azide is nitrogen. 2NaN₃(s)→ 2Na(s)+ 3N₂(g)
What mass of NaN₃ is required to inflate a bag with a volume of 45 L at a pressure of 1.0 atm and a temperature of 305 K? The gas law constant is 0.0821 L⋅atm/mol⋅K and the molar mass of NaN₃ is 65.0 g/mol.

A) 2.8 × 10−² g
B) 1.2 × 10−¹ g
C) 7.8 × 10¹ g
D) 1.2 × 10² g
E) 1.8 × 10² g

Question 48

Ilmenite,an ore used in the production of metallic titanium,is composed of 36.8% iron,31.6% titanium,and 31.6% oxygen.What is the empirical (simplest)formula for ilmenite?

A) FeTiO
B) FeTiO₂
C) FeTiO₃
D) Fe₂TiO₄
E) Fe₃Ti₂O₆

Question 49

Which of the following cations is a component of vitamin B₁₂?

A) Li⁺
B) Mg²⁺
C) Ca²⁺
D) Co²⁺
E) Hg²⁺

Question 50

Which of the following is the principal cation within cell fluid?

A) Na⁺
B) Mg²⁺
C) K⁺
D) Ca²⁺
E) Fe²⁺

Question 51

Which of the following cations is not a trace species in the human body?

A) Be²⁺
B) Cr³⁺
C) Co²⁺
D) Zn²⁺
E) Cu²⁺