Deck 4: Three Major Classes of Chemical Reactions

Question 1

How many moles of H⁺(aq) ions are present in 1.25 L of 0.75 M nitric acid?

A) 0.60 mol
B) 0.75 mol
C) 0.94 mol
D) 1.7 mol
E) 1.9 mol

Answer 1

0.94 mol

Question 2

Which one of the following ionic compounds is soluble in water?

A) Na₂S
B) PbI₂
C) AgCl
D) CuS
E) Ca₃(PO₄)₂

Answer 2

Na₂S

Question 3

Select the precipitate that forms when the following reactants are mixed. Na₂CO₃(aq) + BaCl₂(aq) $\rightarrow$

A) Ba₂CO₃
B) BaCO₃
C) NaCl
D) NaCl₂
E) BaO

Answer 3

BaCO₃

Question 4

How many moles of H⁺(aq) ions are present in 750 mL of 0.65 M hydrochloric acid?

A) 1.2 mol
B) 0.98 mol
C) 0.87 mol
D) 0.65 mol
E) 0.49 mol

Question 5

Which of the following will be least soluble in water?

A) potassium sulfate, K₂SO₄
B) ammonium nitrate, NH₄NO₃
C) chloromethane, CH₃Cl
D) calcium chloride, CaCl₂
E) ethanol, C₂H₆O

Question 6

Potassium chloride, KCl, sodium sulfate, Na₂SO₄, glucose, C₆H₁₂O₆, carbon dioxide, CO₂ and ammonium phosphate, (NH₄)₃PO₄, are soluble in water. Which one produces the largest number of dissolved particles per mole of dissolved solute?

A) KCl
B) Na₂SO₄
C) C₆H₁₂O₆
D) CO₂
E) (NH₄)₃PO₄

Question 7

Magnesium carbonate, MgCO₃, is insoluble. Identify the spectator ions when aqueous solutions of sodium carbonate and magnesium chloride are combined.

A) Mg²⁺ and CO₃^2¯
B) Na⁺ and Cl^¯
C) Mg²⁺ and Cl^¯
D) Na⁺ and CO₃^2¯
E) None of these choices correctly identifies the spectator ions.

Question 8

Which one of the following substances, when dissolved in water at equal molar concentrations, will give the solution with the lowest electrical conductivity?

A) CaCl₂
B) HNO₃
C) NH₃
D) C₆H₁₂O₆ (glucose)
E) CO₂

Question 9

How many moles of ions are released when 0.27 mol of cobalt(II) chloride, CoCl₂, is dissolved in water?

A) 0.81 mol
B) 0.54 mol
C) 0.27 mol
D) 0.18 mol
E) 0.090 mol

Question 10

Which of the following solutions will be the best conductor of electrical current?

A) methyl alcohol, CH₃OH(aq)
B) glucose, C₆H₁₂O₆(aq)
C) potassium chloride, KCl(aq)
D) bromine, Br₂(aq)
E) ethylene glycol, C₂H₆O₂(aq)

Question 11

Which of the following solutions will be the poorest conductor of electrical current?

A) sucrose, C₁₂H₂₂O₁₁(aq)
B) sodium chloride, NaCl(aq)
C) potassium nitrate, KNO₃(aq)
D) lithium hydroxide, LiOH(aq)
E) sulfuric acid, H₂SO₄(aq)

Question 12

Potassium carbonate, K₂CO₃, sodium iodide, NaI, magnesium chloride, MgCl₂, methanol, CH₃OH, and ammonium chloride, NH₄Cl, are soluble in water. Which produces the largest number of dissolved particles per mole of dissolved solute?

A) K₂CO₃
B) NaI
C) MgCl₂
D) CH₃OH
E) NH₄Cl

Question 13

Which of the following is most soluble in water?

A) benzene, C₆H₆
B) potassium nitrate, KNO₃
C) carbon tetrachloride, CCl₄
D) hexane, C₆H₁₄
E) ethane, C₂H₄

Question 14

Which one of the following ionic compounds is insoluble in water?

A) Na₃PO₄
B) AgNO₃
C) NaCl
D) CaCO₃
E) MgCl₂

Question 15

What, if any, are the spectator ions when aqueous solutions of HBr and RbOH neutralize each other?

A) H⁺ and OH^¯
B) H⁺ and Rb⁺
C) Rb⁺ and Br^¯
D) Br^¯ and OH^¯
E) There are no spectator ions in this reaction.

Question 16

1.0 M aqueous solutions of the following substances are prepared. Which one would you expect to have the lowest electrical conductivity?

A) NaOH
B) CH₃CH₂OH (ethanol)
C) KBr
D) CH₃COOH (acetic acid)
E) HClO₄

Question 17

Which one of the following substances is the best electrolyte?

A) CO
B) CH₃Cl
C) CH₄
D) C₂H₅OH
E) HCl

Question 18

How many sodium ions are present in 325 mL of 0.850 M Na₂SO₄?

A) 1.66 * 10²³ sodium ions
B) 3.33 *10²³ sodium ions
C) 4.99 * 10²³ sodium ions
D) 6.20* 10²³ sodium ions
E) 1.57 *10²⁴ sodium ions

Question 19

How many moles of ions are released when 1.6 mol of ammonium phosphate, (NH₄)₃PO₄, is dissolved in water?

A) 0.40 mol
B) 1.6 mol
C) 3.2 mol
D) 4.8 mol
E) 6.4 mol

Question 20

In the following reaction, what ions, if any, are spectator ions? Pb(NO₃)₂(aq) + 2NaCl(aq) $\rightarrow$ PbCl₂(s) + 2NaNO₃(aq)

A) Pb²⁺(aq), Cl^¯(aq)
B) Na⁺(aq), NO₃^¯(aq)
C) Pb²⁺(aq), NO₃^¯(aq)
D) Na⁺(aq), Cl^¯(aq)
E) There are no spectator ions in this reaction.

Question 21

Which of the following is a weak base?

A) NH₃
B) Ca(OH)₂
C) Ba(OH)₂
D) NaOH
E) CH₃COOH

Question 22

Which of the following is a strong base?

A) NH₃
B) Ca(OH)₂
C) Al(OH)₃
D) B(OH)₃
E) CH₃OH

Question 23

A standard solution of 0.243 M NaOH was used to determine the concentration of a hydrochloric acid solution. If 46.33 mL of NaOH is needed to neutralize 10.00 mL of the acid, what is the molar concentration of the acid?

A) 0.0524 M
B) 0.888 M
C) 1.13 M
D) 2.26 M
E) 2.43 M

Question 24

Select the correct name and chemical formula for the precipitate that forms when the following reactants are mixed. CoSO₄(aq) + (NH₄)₃PO₄(aq) $\rightarrow$

A) cobalt(II) phosphate, Co₃(PO₄)₂
B) cobalt(III) phosphate, Co₃(PO₄)₂
C) cobalt(II) phosphate, CoPO₄
D) cobalt(III) phosphate, CoPO₄
E) ammonium sulfate, (NH₄)₂SO₄

Question 25

Which one of the following substances is a strong acid?

A) HNO₃
B) H₂CO₃
C) NH₃
D) CH₃COOH
E) H₃PO₄

Question 26

Select the precipitate that forms when the following reactants are mixed. Mg(CH₃COO)₂(aq) + LiOH(aq) $\rightarrow$

A) LiCH₃COO
B) Li(CH₃COO)₂
C) MgOH
D) Mg(OH)₂
E) CH₃OH

Question 27

Which of the following is a strong acid?

A) H₃PO₄
B) HNO₃
C) HF
D) CH₃COOH
E) H₂O

Question 28

An acid

A) produces hydroxide ions when dissolved in water.
B) changes the color of phenolphthalein indicator from colorless to pink.
C) donates electrons in an electron transfer reaction.
D) donates protons in a proton transfer reaction.
E) does none of these choices.

Question 29

Select the correct name and chemical formula for the precipitate that forms when the following reactants are mixed. CuCl₂(aq) + Na₂CO₃(aq) $\rightarrow$

A) copper(I) carbonate, Cu₂CO₃
B) copper(II) carbonate, Cu₂CO₃
C) copper(I) carbonate, CuCO₃
D) copper(II) carbonate, CuCO₃
E) sodium chloride, NaCl

Question 30

Select the precipitate that forms when aqueous ammonium sulfide reacts with aqueous copper(II) nitrate.

A) CuS
B) Cu₂S
C) NH₄NO₃
D) NH₄(NO₃)₂
E) CuSO₄

Question 31

Select the precipitate that forms when aqueous lead(II) nitrate reacts with aqueous sodium sulfate.

A) NaNO₃
B) Na₂NO₃
C) PbSO₄
D) Pb₂SO₄
E) PbS

Question 32

A base

A) causes phenolphthalein indicator to change from colorless to pink.
B) donates a proton in a proton transfer reaction.
C) accepts electrons in an electron transfer reaction.
D) produces hydrogen ions in solution.
E) does none of these choices.

Question 33

Select the correct set of products for the following reaction. Ba(OH)₂(aq) + HNO₃(aq) $\rightarrow$

A) BaN₂(s) + H₂O(l)
B) Ba(NO₃)₂(aq) + H₂O(l)
C) Ba(s) + H₂(g) + NO₂(g)
D) Ba₂O(s) + NO₂(g) + H₂O(l)
E) No reaction occurs.

Question 34

Which, if any, of the following properties applies to weak acids?

A) They are strong electrolytes.
B) They are excellent conductors of electricity.
C) When dissolved in water, they do not ionize completely.
D) All of these choices are correct.
E) None of these choices is correct.

Question 35

Select the net ionic equation for the reaction between lithium hydroxide and hydrobromic acid. LiOH(aq) + HBr(aq) $\rightarrow$ H₂O(l) + LiBr(aq)

A) LiOH(aq) $\rightarrow$ Li⁺(aq) + OH^¯(aq)
B) HBr(aq) $\rightarrow$ H⁺(aq) + Br^¯(aq)
C) H⁺(aq) + OH^¯(aq) $\rightarrow$ H₂O(l)
D) Li⁺(aq) + Br^¯(aq) $\rightarrow$ LiBr(aq)
E) Li⁺(aq) + OH^¯(aq) + H⁺(aq) + Br^¯(aq) $\rightarrow$ H₂O(l) + LiBr(aq)

Question 36

Consider the reaction: 3Co²⁺(aq) + 6NO₃^¯(aq) + 6Na⁺(aq) + 2PO₄^3¯(aq) $\rightarrow$
Co₃(PO₄)₂(s) + 6Na⁺(aq) + 6NO₃^¯(aq)
Identify the net ionic equation for this reaction.

A) Na⁺(aq) + NO₃^¯(aq) $\rightarrow$ NaNO₃(aq)
B) 3Co²⁺(aq) + NO₃^¯(aq) + Na⁺(aq) + 2PO₄^3¯(aq) $\rightarrow$ Co₃(PO₄)₂(s) + NaNO₃(aq)
C) 3Co²⁺(aq) + 6NO₃^¯(aq) + 6Na⁺(aq) + 2PO₄^3¯(aq) $\rightarrow$ Co₃(PO₄)₂(s) + 6NaNO₃(aq)
D) 3Co²⁺(aq) + 2PO₄^3¯(aq) $\rightarrow$ Co₃(PO₄)₂(s)
E) None of these choices is correct.

Question 37

Which of the following is a weak acid?

A) H₂SO₄
B) HNO₃
C) HF
D) HBr
E) HCl

Question 38

Select the net ionic equation for the reaction between sodium chloride and mercury(I) nitrate. 2NaCl(aq) + Hg₂(NO₃)₂(aq) $\rightarrow$ NaNO₃(aq) + Hg₂Cl₂(s)

A) Na⁺(aq) + NO₃^¯(aq) $\rightarrow$ NaNO₃(aq)
B) Hg₂²⁺(aq) + 2Cl^¯(aq) $\rightarrow$ Hg₂Cl₂(s)
C) NaCl(aq) $\rightarrow$ Na⁺(aq) + Cl^¯(aq)
D) Hg₂(NO₃)₂(aq) $\rightarrow$ Hg₂²⁺(aq) + 2NO₃^¯(aq)
E) Hg₂²⁺(aq) $\rightarrow$ Hg₂(s)

Question 39

Ammonia, NH₃, produces hydroxide ions in aqueous solution by

A) donating a proton to an acid molecule.
B) donating a proton to a water molecule.
C) donating a hydrogen ion to a water molecule.
D) accepting an electron from an acid molecule.
E) accepting a proton from a water molecule.

Question 40

Automobile batteries use 3.0 M H₂SO₄ as an electrolyte. How much 1.20 M NaOH will be needed to neutralize 225 mL of battery acid? H₂SO₄(aq) + 2NaOH(aq) $\rightarrow$ 2H₂O(l) + Na₂SO₄(aq)

A) 0.045 L
B) 0.28 L
C) 0.56 L
D) 0.90 L
E) 1.1 L

Question 41

Identify the oxidizing agent in the following redox reaction. Hg²⁺(aq) + Cu(s) $\rightarrow$ Cu²⁺(aq) + Hg(l)

A) Hg²⁺(aq)
B) Cu(s)
C) Cu²⁺(aq)
D) Hg(l)
E) Hg²⁺(aq) and Cu²⁺(aq)

Question 42

Which one of the following is not a redox reaction?

A) 2H₂O₂(aq) $\rightarrow$ 2H₂O(l) + O₂(g)
B) N₂(g) + 3H₂(g) $\rightarrow$ 2NH₃(g)
C) BaCl₂(aq) + K₂CrO₄(aq) $\rightarrow$ BaCrO₄(aq) + 2KCl(aq)
D) 2Al(s) + Fe₂O₃(s) $\rightarrow$ Al₂O₃(s) + 2Fe(s)
E) 2H₂O(g) $\rightarrow$ 2H₂(g) + O₂(g)

Question 43

Sodium thiosulfate, Na₂S₂O₃, is used as a "fixer" in black and white photography. Identify the reducing agent in the reaction of thiosulfate with iodine. 2S₂O₃^2¯(aq) + I₂(aq) $\rightarrow$ S₄O₆^2¯(aq) + 2I^¯(aq)

A) I₂(aq)
B) I^¯(aq)
C) S₂O₃^2¯(aq)
D) S₄O₆^2¯(aq)
E) S₂O₃^2¯(aq) and I^¯(aq)

Question 44

Sodium tripolyphosphate is used in detergents to make them effective in hard water. Calculate the oxidation number of phosphorus in Na₅P₃O₁₀.

A) +3
B) +5
C) +10
D) +15
E) None of these choices is correct.

Question 45

Which one of the following is a redox reaction?

A) 2Na(g) + Cl₂(g) $\rightarrow$ 2NaCl(s)
B) Ba²⁺(aq) + SO₄^2¯(aq) $\rightarrow$ BaSO₄(s)
C) K₂Cr₂O₇(aq) + 2KOH(aq) $\rightarrow$ 2K₂CrO₄(aq) + H₂O(l)
D) Na₂CO₃(s) + 2HCl(aq) $\rightarrow$ 2NaCl(aq) + CO₂(g) + H₂O(l)
E) H₂O(l) $\rightarrow$ H⁺(aq) + OH^¯(aq)

Question 46

What is the oxidation number of iodine in I₂.

A) -1
B) 0
C) +1
D) +7
E) None of these choices is correct.

Question 47

Vinegar is a solution of acetic acid, CH₃COOH, dissolved in water. A 5.54-g sample of vinegar was neutralized by 30.10 mL of 0.100 M NaOH. What is the percent by weight of acetic acid in the vinegar?

A) 0.184%
B) 1.63%
C) 3.26%
D) 5.43%
E) 9.23%

Question 48

Which one of the following is not a redox reaction?

A) 2H₂(g) + O₂(g) $\rightarrow$ 2H₂O(l)
B) Zn(s) + H₂SO₄(aq) $\rightarrow$ ZnSO₄(aq) + H₂(g)
C) H₂O(l) + NH₃(g) $\rightarrow$ NH₄⁺(aq) + OH^¯(aq)
D) 6FeSO₄(aq) + K₂Cr₂O₇(aq)+ 7H₂SO₄(aq) $\rightarrow$ Cr₂(SO₄)₃(aq) + 3Fe₂(SO₄)₃(aq)+ K₂SO₄(aq) + 7H₂O(l)
E) Cl₂(g) + 2KBr(aq) $\rightarrow$ Br₂(l) + 2KCl(aq)

Question 49

Balance the following redox equation using the smallest integers possible and select the correct coefficient for the hydrogen sulfite ion, HSO₃^¯. MnO₄^¯(aq) + HSO₃^¯(aq) + H⁺(aq) $\rightarrow$ Mn²⁺(aq) + SO₄^2¯(aq) + H₂O(l)

A) 1
B) 2
C) 3
D) 5
E) 10

Question 50

Calculate the oxidation number of the chlorine in perchloric acid, HClO₄, a strong oxidizing agent.

A) -1
B) +4
C) +5
D) +7
E) None of these choices is correct.

Question 51

Select the best statement relating to the following reaction: 2MnO₂(s) + KClO₃(aq) + 2KOH(aq) $\rightarrow$ 2KMnO₄(aq) + KCl(aq) + H₂O(l)

A) Mn in MnO₂ is oxidized.
B) O in KClO₃ is the oxidizing agent.
C) K in KClO₃ is the reducing agent.
D) H in KOH is oxidized.
E) Cl in KClO₃ is the reducing agent.

Question 52

Identify all the spectator ions in the following reaction. 2KMnO₄(aq) + 10FeSO₄(aq) + 8H₂SO₄(aq) $\rightarrow$
K₂SO₄(aq) + 2MnSO₄(aq) + 5Fe₂(SO₄)₃(aq) + 8H₂O(l)

A) only K⁺
B) only SO₄^2¯
C) only K⁺ and SO₄^2¯
D) only K⁺, SO₄^2¯ and Fe²⁺
E) only K⁺, SO₄^2¯, Fe²⁺ and Mn²⁺

Question 53

Which of the statements below correctly describes the combustion of glucose, shown below? C₆H₁₂O₆ + 6O₂ $\rightarrow$ 6CO₂ + 6H₂O

A) Hydrogen in C₆H₁₂O₆ is being reduced.
B) Oxygen in O₂ is being oxidized.
C) Hydrogen in C₆H₁₂O₆ is the reducing agent.
D) Oxygen in C₆H₁₂O₆ is the oxidizing agent.
E) Carbon in C₆H₁₂O₆ is being oxidized.

Question 54

A 0.00100 mol sample of Ca(OH)₂ requires 25.00 mL of aqueous HCl for neutralization according to the reaction below. What is the concentration of the HCl? Equation: Ca(OH)₂(s) + 2HCl(aq) $\rightarrow$ CaCl₂(aq) + H₂O(l)

A) 0.0200 M
B) 0.0400 M
C) 0.0800 M
D) 4.00 *10^¯5 M
E) None of these choices is correct.

Question 55

In a redox reaction, electrons are transferred

A) from the substance being oxidized to the reducing agent.
B) from the oxidizing agent to the reducing agent.
C) from the substance being reduced to the oxidizing agent.
D) from the substance being oxidized to the substance being reduced.
E) from the substance being reduced to the substance being oxidized.

Question 56

Balance the following redox equation using the smallest integers possible and select the correct coefficient for the iron(II) hydroxide, Fe(OH)₂. Fe(OH)₂(s) + CrO₄^2¯(aq) $\rightarrow$ Fe₂O₃(s) + Cr(OH)₄^¯(aq) + H₂O(l) + OH^¯(aq)

A) 1
B) 2
C) 3
D) 4
E) 6

Question 57

Which one of the following is not a redox reaction?

A) 2Na(s) + 2H₂O(l) $\rightarrow$ 2NaOH(aq) + H₂(g)
B) H₂(g) + Cl₂(g) $\rightarrow$ 2HCl(g)
C) 2H₂O₂(aq) $\rightarrow$ 2H₂O(l) + O₂(g)
D) Fe₂O₃(s) + 3H₂SO₄(aq) $\rightarrow$ Fe₂(SO₄)₃(aq) + 3H₂O(l)
E) 2KMnO₄(aq) + 10FeSO₄(aq) + 8H₂SO₄(aq) $\rightarrow$ K₂SO₄(aq) + 2MnSO₄(aq) + 5Fe₂(SO₄)₃(aq) + 8H₂O(l)

Question 58

The oxidation numbers of P, S and Cl in H₂PO₂^¯, H₂S and KClO₄ are, respectively

A) -1, -1, +3
B) +1, -2, +7
C) +1, +2, +7
D) -1, -2, +7
E) -1, -2, +3

Question 59

Balance the following redox equation using the smallest integers possible and select the correct coefficient for the chromate anion, CrO₄^2¯. CrO₄^2¯(aq) + CN^¯(aq) + H₂O(l) $\rightarrow$ CNO^¯(aq) + Cr(OH)₄^¯(aq) + OH^¯(aq)

A) 1
B) 2
C) 3
D) 5
E) 6

Question 60

Calculate the oxidation number of sulfur in sodium metabisulfite, Na₂S₂O₅.

A) -2
B) +2
C) +4
D) +5
E) None of these choices is correct.

Question 61

Select the classification for the following reaction.

A) displacement
B) decomposition
C) combination
D) precipitation
E) acid-base

Question 62

Select the classification for the following reaction: 2H₂O₂(aq) $\rightarrow$ 2H₂O(l) + O₂(g)

A) combination
B) decomposition
C) displacement
D) acid-base
E) None of these choices is correct.

Question 63

Predict the product(s) for the following reaction:

A) Ba(s) + CO₃(g)
B) BaCO₃(s)
C) BaO(s) + C(s)
D) Ba(s) + CO₃^2¯(s)
E) No reaction occurs.

Question 64

Select the classification for the following reaction. 2Na(s) + 2H₂O(l) $\rightarrow$ 2NaOH(aq) + H₂(g)

A) precipitation
B) acid-base
C) redox
D) combination
E) None of these choices is correct.

Question 65

Select the classification for the following reaction:

A) acid-base
B) precipitation
C) combination
D) displacement
E) decomposition

Question 66

Select the classification for the following reaction: Na₂O(s) + H₂O(l) $\rightarrow$ 2NaOH(aq)

A) combination
B) decomposition
C) displacement
D) acid-base
E) precipitation

Question 67

Predict the product(s) for the following reaction:

A) HClO₄(aq)
B) H₂ClO₄(aq)
C) H(ClO₄)₂(aq)
D) HCl(aq) + O₂(g)
E) HClO₃(aq)

Question 68

Select the classification for the following reaction: H₂(g) + Cl₂(g) $\rightarrow$ 2HCl(g)

A) combination
B) decomposition
C) displacement
D) acid-base
E) None of these choices is correct.

Question 69

Balance the following redox equation using the smallest integers possible and select the correct coefficient for the bromide anion, Br^¯. Br₂(aq) + OH^¯(aq) $\rightarrow$ Br^¯(aq) + BrO₃^¯(aq) + H₂O(l)

A) 1
B) 2
C) 5
D) 6
E) 10

Question 70

Select the classification for the following reaction: KOH(aq) + HCl(aq) $\rightarrow$ KCl(aq) + H₂O(l)

A) precipitation
B) acid-base
C) redox
D) combination
E) None of these choices is correct.

Question 71

Predict the product(s) for the following reaction:

A) K₂SO₄(aq) + H₂O(l)
B) K₂S(aq) + H₂O(l)
C) K(s) + H₂(g) + SO₃(g)
D) KSO₄(aq) + H₂O(l)
E) No reaction occurs.

Question 72

Select the classification for the following reaction: Fe(s) + 2Fe³⁺(aq) $\rightarrow$ 3Fe²⁺(aq)

A) precipitation
B) acid-base
C) redox
D) decomposition
E) None of these choices is correct.

Question 73

Select the classification for the following reaction: Fe²⁺(aq) + 2OH^¯(aq) $\rightarrow$ Fe(OH)₂(s)

A) precipitation
B) acid-base
C) redox
D) decomposition
E) None of these choices is correct.

Question 74

The amount of calcium present in milk can be determined by adding oxalate to a sample and measuring the mass of calcium oxalate precipitated. What is the mass percent of calcium if 0.429 g of calcium oxalate forms in a 125-g sample of milk when excess aqueous sodium oxalate is added? Na₂C₂O₄(aq) + Ca²⁺(aq) $\rightarrow$ CaC₂O₄(s) + 2Na⁺(aq)

A) 0.107%
B) 0.202%
C) 0.343%
D) 1.10%
E) 1.37%

Question 75

Select the classification for the following reaction.

A) combination
B) decomposition
C) displacement
D) acid-base
E) precipitation

Question 76

Select the classification for the following reaction: NH₃(aq) + HNO₃(aq) $\rightarrow$ NH₄NO₃(aq)

A) precipitation
B) acid-base
C) redox
D) decomposition
E) None of these choices is correct.

Question 77

Select the classification for the following reaction: BaCl₂(aq) + K₂SO₄(aq) $\rightarrow$ BaSO₄(s) + 2KCl(aq)

A) precipitation
B) acid-base
C) redox
D) decomposition
E) None of these choices is correct.

Question 78

Select the classification for the following reaction.

A) combination
B) displacement
C) decomposition
D) precipitation
E) acid-base

Question 79

The compound P₄O₁₀ is used in refining sugar. Select the classification for the reaction in which it is synthesized. P₄(s) + 5O₂(g) $\rightarrow$ P₄O₁₀(s)

A) combination
B) decomposition
C) displacement
D) acid-base
E) precipitation

Question 80

Select the classification for the following reaction: H₂CO₃(aq) $\rightarrow$ H₂O(l) + CO₂(g)

A) combination
B) decomposition
C) displacement
D) acid-base
E) None of these choices is correct.