Question 1

According to the following balanced reaction,how many moles of KO are required to exactly react with 5.44 moles of H₂O? 4 KO(s)+ 2 H₂O(l)→ 4 KOH(s)+ O₂(g)

Accepted Answer

According to the balanced reaction, 4 moles of KO react with 2 moles of H₂O. This means that to completely react with 1 mole of H₂O, we need 4/2 = 2 moles of KO. Therefore, to exactly react with 5.44 moles of H₂O, we will need 5.44 x 2 = 10.88 moles of KO. Rounded to the nearest tenth, this is 10.9 moles of KO, which is answer choice B.

Question 2

What is the oxidation number of the sulfur atom in Li₂SO₄?

Accepted Answer

The given chemical formula is for lithium sulfate, Li2SO4. In this compound, sulfur has an oxidation state of +6, as oxygen has a -2 oxidation state and lithium has a +1 oxidation state, balancing the overall charge to zero.

Question 3

How many aluminum ions are present in 65.5 mL of 0.210 M AlF₃ solution?

Accepted Answer

The answer of How many aluminum ions are present in...

Question 4

Which substance is oxidized in the following reaction? 5C₂O₄^2- + 2MnO₄^-+ 16H⁺ → 10 CO₂ + 2Mn²⁺ + 4H₂O)

Accepted Answer

C₂O₄^2- is oxidized to CO₂ as it loses electrons (increase in oxidation state of carbon from +3 to +4).

Question 5

1.06g of Na₂CO₃ is dissolved in 100mL of water.What is the molarity of Na⁺ions in the solution?

Accepted Answer

The molarity of Na+ ions in the solution is 0.2 M. This is because Na2CO3 dissociates into 2 Na+ ions and 1 CO32- ion in water. Therefore, the molarity of Na+ ions is twice the molarity of Na2CO3, which is 0.1 M.

Question 6

Nitrogen dioxide reacts with water to form nitric acid and nitrogen monoxide according to the equation: 3 NO₂(g)+ H₂O(l)→ HNO₃(l)+ NO(g) Suppose that 4 mol NO₂ and 2 H₂O mol combine and react completely.How many Moles of NO are produced after the reaction has completed?

Accepted Answer

The answer of Nitrogen dioxide reacts with water to form...

Question 7

Which statement is correct for the following redox reaction? 5 Fe²⁺ + MnO₄^-+8H⁺ → 5 Fe³⁺+Mn²⁺+ 4H₂O

Accepted Answer

In the reaction, MnO₄⁻ is reduced to Mn²⁺, meaning it gains electrons and acts as the oxidizing agent.

Question 8

What mass of N₂ will be produced from the reaction of 50.0 g N₂O₄ with 45.0 g N₂H₄? N₂O₄(l)+ 2 N₂H₄(l)→ 3 N₂(g)+ 4 H₂O(g)

Accepted Answer

The answer of What mass of N₂ will be produced...

Question 9

How many milliliters of 0.132 M HClO₄ solution are needed to neutralize 50.00 mL of 0.0789 M NaOH?

Accepted Answer

The answer of How many milliliters of 0.132 M HClO₄...

Question 10

A solution is prepared by adding 1.60 g of solid NaCl to 50.0 mL of 0.100 M CaCl₂.What is the molarity of chloride ion in the final solution? Assume that the volume of the final solution is 50.0 mL.

Accepted Answer

The answer of A solution is prepared by adding 1.60...

Question 11

What are the spectator ions for the following reaction in aqueous solution: AgNO₃(aq)+ NaCl(aq)→ AgCl(s)+ NaNO₃(aq)

Accepted Answer

Na⁺ and NO₃^- are spectator ions because they do not participate in the formation of the precipitate AgCl and remain in the aqueous solution.

Question 12

What are the coefficients in front of NO₃^-(aq)and Cu(s)when the following redox equation is balanced in an acidic solution: ____ NO₃^-(aq)+ ____ Cu(s)→ ____ NO(g)+ ____ Cu²⁺(aq)?

Accepted Answer

In order to balance the equation, the number of electrons lost by Cu must equal the number of electrons gained by NO₃^-(aq). This requires the coefficient of Cu to be 3 and the coefficient of NO₃^-(aq) to be 2. Therefore, the coefficients in front of Cu and NO₃^-(aq) are 3 and 2, respectively.

Question 13

What is the oxidation number of the chromium atom in Na₂CrO₄?

Accepted Answer

The oxidation numbers of sodium, sulfur, and oxygen are +1, -2, and -2 respectively. The sum of the oxidation numbers of all the atoms in a compound is equal to the overall charge of the compound, which is 0 in this case. Let x be the oxidation number of chromium. Then we have:
(+1) + (-2) + 12(-1) + (-2) + x + 14(-1) + (-2) = 0
Solving for x, we get:
x = +6
Therefore, the oxidation number of the chromium atom is +6, which corresponds to choice C.

Question 14

What is the molarity of a NaOH solution if 28.2 mL of a 0.355 M H₂SO₄ solution is required to neutralize a 25.0-mL sample of the NaOH solution?

Accepted Answer

The answer of What is the molarity of a NaOH...

Question 15

What is the oxidation number change for the bromine atom in the following unbalanced reduction half reaction: BrO₃^-(aq)+ H⁺(aq)→ Br^-(aq)+ H₂O(l)?

Accepted Answer

The answer of What is the oxidation number change for...

Question 16

Nitrogen dioxide reacts with water to form nitric acid and nitrogen monoxide according to the equation: 3 NO₂(g)+ H₂O(l)→ HNO₃(l)+ NO(g) Suppose that 4mol NO₂ and 2 H₂O mol combine and react completely.How many Moles of the reactant in excess are present after the reaction has completed?

Accepted Answer

The answer of Nitrogen dioxide reacts with water to form...

Question 17

What is the oxidation number of the oxygen atom in Rb₂O₂?

Accepted Answer

In Rb₂O₂, the compound is a peroxide. In peroxides, oxygen has an oxidation number of -1.

Question 18

How many milliliters of a 0.266 M NaNO₃ solution are required to make 150.0 mL of 0.075 M NaNO₃ solution?

Accepted Answer

First, we need to use the formula: M1V1 = M2V2 where: M1 = 0.266 M (the concentration of the stock solution) V1 = unknown (the volume of the stock solution we need to use) M2 = 0.075 M (the concentration we want to achieve) V2 = 150.0 mL (the final volume of the solution) Rearranging the equation, we get: V1 = (M2V2)/M1 V1 = (0.075 mol/L) x (0.150 L) / (0.266 mol/L) V1 = 0.0423 L or 42.3 mL Therefore, we need 42.3 mL of the 0.266 M NaNO₃ solution to make 150.0 mL of 0.075 M NaNO₃ solution.

Question 19

What is the net ionic reaction for the following reaction in aqueous solutions: AgNO₃(aq)+ NaCl(aq)→ AgCl(s)+ NaNO₃(aq)

Accepted Answer

The net ionic reaction shows the species that actually participate in the reaction, ignoring spectator ions. In this case, the spectator ions are Na+ and NO3-. The net ionic reaction can be obtained by identifying the species that are aqueous and not identical on each side of the equation and then canceling out any spectator ions that appear on both sides. 
Ag+(aq) + Cl-(aq) → AgCl(s)

Quiz 4: Chemical Quantities and Aqueous Reactions

According to the following balanced reaction,how many moles of KO are required to exactly react with 5.44 moles of H₂O? 4 KO(s) + 2 H₂O(l) → 4 KOH(s) + O₂(g)

What is the oxidation number of the sulfur atom in Li₂SO₄?

How many aluminum ions are present in 65.5 mL of 0.210 M AlF₃ solution?

Which substance is oxidized in the following reaction? 5C₂O₄^2- + 2MnO₄^-+ 16H⁺ → 10 CO₂ + 2Mn²⁺ + 4H₂O)

1.06g of Na₂CO₃ is dissolved in 100mL of water.What is the molarity of Na⁺ions in the solution?

Nitrogen dioxide reacts with water to form nitric acid and nitrogen monoxide according to the equation: 3 NO₂(g) + H₂O(l) → HNO₃(l) + NO(g) Suppose that 4 mol NO₂ and 2 H₂O mol combine and react completely.How many Moles of NO are produced after the reaction has completed?

Which statement is correct for the following redox reaction? 5 Fe²⁺ + MnO₄^-+8H⁺ → 5 Fe³⁺+Mn²⁺+ 4H₂O

What mass of N₂ will be produced from the reaction of 50.0 g N₂O₄ with 45.0 g N₂H₄? N₂O₄(l) + 2 N₂H₄(l) → 3 N₂(g) + 4 H₂O(g)

How many milliliters of 0.132 M HClO₄ solution are needed to neutralize 50.00 mL of 0.0789 M NaOH?

A solution is prepared by adding 1.60 g of solid NaCl to 50.0 mL of 0.100 M CaCl₂.What is the molarity of chloride ion in the final solution? Assume that the volume of the final solution is 50.0 mL.

What are the spectator ions for the following reaction in aqueous solution: AgNO₃(aq) + NaCl(aq) → AgCl(s) + NaNO₃(aq)

What are the coefficients in front of NO₃^-(aq) and Cu(s) when the following redox equation is balanced in an acidic solution: NO₃^-(aq) + Cu(s) → NO(g) + Cu²⁺(aq) ?

What is the oxidation number of the chromium atom in Na₂CrO₄?

What is the molarity of a NaOH solution if 28.2 mL of a 0.355 M H₂SO₄ solution is required to neutralize a 25.0-mL sample of the NaOH solution?

What is the oxidation number change for the bromine atom in the following unbalanced reduction half reaction: BrO₃^-(aq) + H⁺(aq) → Br^-(aq) + H₂O(l) ?

What is the oxidation number of the oxygen atom in Rb₂O₂?

How many milliliters of a 0.266 M NaNO₃ solution are required to make 150.0 mL of 0.075 M NaNO₃ solution?

What is the net ionic reaction for the following reaction in aqueous solutions: AgNO₃(aq) + NaCl(aq) → AgCl(s) + NaNO₃(aq)

Quiz 4: Chemical Quantities and Aqueous Reactions

According to the following balanced reaction,how many moles of KO are required to exactly react with 5.44 moles of H2O? 4 KO(s) + 2 H2O(l) → 4 KOH(s) + O2(g)

What is the oxidation number of the sulfur atom in Li2SO4?

How many aluminum ions are present in 65.5 mL of 0.210 M AlF3 solution?

Which substance is oxidized in the following reaction? 5C2O42- + 2MnO4- + 16H+ → 10 CO2 + 2Mn2+ + 4H2O)

1.06g of Na2CO3 is dissolved in 100mL of water.What is the molarity of Na+ ions in the solution?

Nitrogen dioxide reacts with water to form nitric acid and nitrogen monoxide according to the equation: 3 NO2(g) + H2O(l) → HNO3(l) + NO(g) Suppose that 4 mol NO2 and 2 H2O mol combine and react completely.How many Moles of NO are produced after the reaction has completed?

Which statement is correct for the following redox reaction? 5 Fe2+ + MnO4- +8H+ → 5 Fe3+ +Mn2+ + 4H2O

What mass of N2 will be produced from the reaction of 50.0 g N2O4 with 45.0 g N2H4? N2O4(l) + 2 N2H4(l) → 3 N2(g) + 4 H2O(g)

How many milliliters of 0.132 M HClO4 solution are needed to neutralize 50.00 mL of 0.0789 M NaOH?

A solution is prepared by adding 1.60 g of solid NaCl to 50.0 mL of 0.100 M CaCl2.What is the molarity of chloride ion in the final solution? Assume that the volume of the final solution is 50.0 mL.

What are the spectator ions for the following reaction in aqueous solution: AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq)

What are the coefficients in front of NO3-(aq) and Cu(s) when the following redox equation is balanced in an acidic solution: ____ NO3-(aq) + ____ Cu(s) → ____ NO(g) + ____ Cu2+(aq) ?

What is the oxidation number of the chromium atom in Na2CrO4?

What is the molarity of a NaOH solution if 28.2 mL of a 0.355 M H2SO4 solution is required to neutralize a 25.0-mL sample of the NaOH solution?

What is the oxidation number change for the bromine atom in the following unbalanced reduction half reaction: BrO3-(aq) + H+(aq) → Br-(aq) + H2O(l) ?

Nitrogen dioxide reacts with water to form nitric acid and nitrogen monoxide according to the equation: 3 NO2(g) + H2O(l) → HNO3(l) + NO(g) Suppose that 4mol NO2 and 2 H2O mol combine and react completely.How many Moles of the reactant in excess are present after the reaction has completed?

What is the oxidation number of the oxygen atom in Rb2O2?

How many milliliters of a 0.266 M NaNO3 solution are required to make 150.0 mL of 0.075 M NaNO3 solution?

What is the net ionic reaction for the following reaction in aqueous solutions: AgNO3(aq) + NaCl(aq) → AgCl(s) + NaNO3(aq)

According to the following balanced reaction,how many moles of KO are required to exactly react with 5.44 moles of H₂O? 4 KO(s) + 2 H₂O(l) → 4 KOH(s) + O₂(g)

What is the oxidation number of the sulfur atom in Li₂SO₄?

How many aluminum ions are present in 65.5 mL of 0.210 M AlF₃ solution?

Which substance is oxidized in the following reaction? 5C₂O₄^2- + 2MnO₄^-+ 16H⁺ → 10 CO₂ + 2Mn²⁺ + 4H₂O)

1.06g of Na₂CO₃ is dissolved in 100mL of water.What is the molarity of Na⁺ions in the solution?

Nitrogen dioxide reacts with water to form nitric acid and nitrogen monoxide according to the equation: 3 NO₂(g) + H₂O(l) → HNO₃(l) + NO(g) Suppose that 4 mol NO₂ and 2 H₂O mol combine and react completely.How many Moles of NO are produced after the reaction has completed?

Which statement is correct for the following redox reaction? 5 Fe²⁺ + MnO₄^-+8H⁺ → 5 Fe³⁺+Mn²⁺+ 4H₂O

What mass of N₂ will be produced from the reaction of 50.0 g N₂O₄ with 45.0 g N₂H₄? N₂O₄(l) + 2 N₂H₄(l) → 3 N₂(g) + 4 H₂O(g)

How many milliliters of 0.132 M HClO₄ solution are needed to neutralize 50.00 mL of 0.0789 M NaOH?

A solution is prepared by adding 1.60 g of solid NaCl to 50.0 mL of 0.100 M CaCl₂.What is the molarity of chloride ion in the final solution? Assume that the volume of the final solution is 50.0 mL.

What are the spectator ions for the following reaction in aqueous solution: AgNO₃(aq) + NaCl(aq) → AgCl(s) + NaNO₃(aq)

What are the coefficients in front of NO₃^-(aq) and Cu(s) when the following redox equation is balanced in an acidic solution: NO₃^-(aq) + Cu(s) → NO(g) + Cu²⁺(aq) ?

What is the oxidation number of the chromium atom in Na₂CrO₄?

What is the molarity of a NaOH solution if 28.2 mL of a 0.355 M H₂SO₄ solution is required to neutralize a 25.0-mL sample of the NaOH solution?

What is the oxidation number change for the bromine atom in the following unbalanced reduction half reaction: BrO₃^-(aq) + H⁺(aq) → Br^-(aq) + H₂O(l) ?

What is the oxidation number of the oxygen atom in Rb₂O₂?

How many milliliters of a 0.266 M NaNO₃ solution are required to make 150.0 mL of 0.075 M NaNO₃ solution?

What is the net ionic reaction for the following reaction in aqueous solutions: AgNO₃(aq) + NaCl(aq) → AgCl(s) + NaNO₃(aq)