Question 1

Complete and balance the equation for the reaction that occurs when H₂SO₄(aq)and NaOH(aq)are mixed.

Accepted Answer

The correct equation is H₂SO₄(aq)+ 2NaOH(aq)→ Na₂SO₄(aq)+ 2H₂O(l). This is a neutralization reaction, in which an acid and a base react to form a salt and water. The coefficients in the equation are balanced so that the number of atoms of each element is the same on both sides of the equation.

Question 2

When balancing a chemical equation, it is acceptable to change the subscripts on the formulas of the skeletal equation.

Accepted Answer

When balancing a chemical equation, the subscripts on the formulas cannot be changed as they represent the ratio of atoms in a molecule. Only coefficients can be added to balance the equation.

Question 3

When powdered sulfur, S₈, burns in air, a purple flame is produced, as well as a toxic, foul-smelling gas. What is the balanced equation for the reaction between sulfur and oxygen gas?

Accepted Answer

The balanced equation for the reaction between sulfur and oxygen gas is:

2S + 3O2 → 2SO3

However, since the question specifies powdered sulfur (S8), the formula needs to be adjusted accordingly:

S8 + 12O2 → 8SO3

The balanced equation in terms of molecules is:

1S8 + 6O2 → 4SO3

But the question asks for the balanced equation in terms of individual atoms, so we need to multiply everything by 8:

8S8 + 48O2 → 32SO3

Which simplifies to:

S16 + 8O2 → 8SO3

Therefore, the correct answer is C, which is the closest to the simplified balanced equation.

Question 4

Complete and balance the equation for the reaction that occurs when HCl(aq)and Mg(OH)₂(aq)are mixed. This reaction occurs in your stomach if you take Milk of Magnesia^®.

Accepted Answer

The answer of Complete and balance the equation for the...

Question 5

When writing an ionic equation, how would Mg(NO₃)₂(aq)be represented?

Accepted Answer

Mg(NO3)2 dissociates into Mg^2+ and 2 NO3^- ions in aqueous solution.

Question 6

Identify the spectator ions in the following reaction: H₂SO₄(aq)+ 2KOH(aq)→ K₂SO₄(aq)+ 2H₂O(l)

Accepted Answer

K⁺(aq) and SO₄²⁻(aq) are spectator ions because they do not participate in the formation of water and remain unchanged in the solution.

Question 7

Identify the spectator ion(s)in the following reaction: Zn(s)+ Cu(NO₃)₂(aq)→ Cu(s)+ Zn(NO₃)₂(aq)

Accepted Answer

Spectator ions do not participate in the chemical reaction and remain in solution unchanged. In this reaction, the nitrate ion (NO3-) is the spectator ion, as it does not change during the reaction from reactants to products.

Question 8

Which of the following is a balanced net ionic equation for the reaction between copper(II)chloride and zinc metal to form copper metal and zinc chloride?

Accepted Answer

The correct net ionic equation for the reaction between copper(II) chloride and zinc metal is $Cu^{2+}(aq) + Zn(s) \rightarrow Cu(s) + Zn^{2+}(aq)$. This equation shows the copper ion being reduced to copper metal and the zinc metal being oxidized to zinc ions, accurately reflecting the exchange of electrons between copper and zinc.

Question 9

When aqueous solutions of K₂CO₃ and CaCl₂ are mixed, what is the correct formula for the precipitate that forms?

Accepted Answer

When aqueous solutions of K2CO3 and CaCl2 are mixed, the precipitate that forms is CaCO3 (calcium carbonate), due to the insolubility of calcium carbonate in water.

Question 10

When one compound is converted into two elements during a chemical reaction, a decomposition reaction has occurred.

Accepted Answer

This is the definition of a decomposition reaction. It involves the breakdown of one compound into two or more simpler substances, which can include elements.

Question 11

Would an aqueous solution of CH₃OH contain ions? If so, indicate the formulas of the ions in the solution.

Accepted Answer

Methanol (CH₃OH) is a molecular compound and does not dissociate into ions in aqueous solution.

Question 12

Would an aqueous solution of KOH contain ions? If so, indicate the formulas of the ions in the solution.

Accepted Answer

Aqueous KOH is a strong base and will dissociate in water to form OH- ions and K+ ions. The formula for OH- ion is OHS1U1P1- and for K+ ion is KS1U1P1+. Therefore, choice D is the correct answer.

Question 13

When acetylene gas, C₂H₂, burns in air, a combustion reaction occurs. Which of the following is a balanced equation that represents this reaction, which occurs when welding torches are used?

Accepted Answer

The balanced equation for the combustion of acetylene (C2H2) in air is 2C2H2(g) + 5O2(g) → 4CO2(g) + 2H2O(g), which matches choice A. This equation correctly represents the complete combustion of acetylene, producing carbon dioxide and water.

Question 14

Would an aqueous solution of K₂SO₄ contain ions? If so, indicate the formulas of the ions in the solution.

Accepted Answer

The presence of the symbol "aq" indicates that the substance is dissolved in water, and therefore can form ions. The formula K₂ can be split into K+ and ₂- ions. Similarly, SO₄ can be split into SO42- and ₄- ions. Therefore, the aqueous solution of K₂SO₄ would contain K+, SO42-, ₂-, and ₄- ions, which are all included in choice D.

Question 15

Sterno, or "canned heat," contains methanol, CH₃OH, and is used for heating containers of food. Which of the following is a balanced equation that represents the combustion reaction that occurs when methanol burns in air?

Accepted Answer

Methanol (CH3OH) is a compound made up of carbon, hydrogen, and oxygen atoms. When methanol burns in air (which contains oxygen, O2), it reacts with oxygen molecules to produce carbon dioxide (CO2) and water (H2O). The balanced chemical equation for this combustion reaction is:
2CH3OH(l) + 3O2(g) → 2CO2(g) + 4H2O(g)
This reaction can be simplified to:
CH3OH(l) + 1.5O2(g) → CO2(g) + 2H2O(g)
However, none of the answer choices match this simplified equation. Only answer choice C has the correct coefficients and products for the combustion of methanol.

Question 16

When aqueous solutions of NaOH and MgCl₂ are mixed, a precipitate forms. What is the correct formula for the precipitate?

Accepted Answer

When NaOH and MgCl2 are mixed, double displacement reaction occurs and Mg(OH)2(s) precipitate forms. The balanced chemical equation for the reaction is:

2NaOH(aq) + MgCl2(aq) → Mg(OH)2(s) + 2NaCl(aq)

Question 17

Which of the following is a balanced net ionic equation for the reaction between iron(II)chloride and potassium hydroxide to form iron(II)hydroxide and potassium chloride?

Accepted Answer

- Fe²⁺(aq) is iron(II) chloride (FeCl2) in aqueous solution - 2OH⁻(aq) is potassium hydroxide (KOH) in aqueous solution - Fe(OH)₂(s) is iron(II) hydroxide (Fe(OH)2) in solid form - The balanced net ionic equation for the reaction is: Fe₂(aq) + 2OH⁻(aq) → Fe(OH)₂(s) + 2Cl⁻(aq)

Question 18

Identify the spectator ions in the following reaction: Zn(s)+ 2HNO₃(aq)→ Zn(NO₃)₂(aq)+ H₂(g)

Accepted Answer

The nitrate ion (NO₃⁻) does not change its oxidation state or participate in the reaction, making it a spectator ion.

Question 19

Complete and balance the equation for the reaction that occurs when HBr(aq)and KOH(aq)are mixed.

Accepted Answer

The reaction between HBr (hydrobromic acid) and KOH (potassium hydroxide) is a neutralization reaction, producing KBr (potassium bromide) and H2O (water). The correct balanced equation is HBr(aq) + KOH(aq) → KBr(aq) + H2O(l).

Question 20

Which of the following is a balanced net ionic equation for the reaction between hydrochloric acid and potassium hydroxid?

Accepted Answer

The balanced net ionic equation for the reaction between hydrochloric acid (HCl) and potassium hydroxide (KOH) is the formation of water from hydrogen ions (H⁺) and hydroxide ions (OH⁻).

Quiz 5: Chemical Reactions and Equations

Complete and balance the equation for the reaction that occurs when H₂SO₄(aq) and NaOH(aq) are mixed.

When balancing a chemical equation, it is acceptable to change the subscripts on the formulas of the skeletal equation.

When powdered sulfur, S₈, burns in air, a purple flame is produced, as well as a toxic, foul-smelling gas. What is the balanced equation for the reaction between sulfur and oxygen gas?

Complete and balance the equation for the reaction that occurs when HCl(aq) and Mg(OH) ₂(aq) are mixed. This reaction occurs in your stomach if you take Milk of Magnesia^®.

When writing an ionic equation, how would Mg(NO₃) ₂(aq) be represented?

Identify the spectator ions in the following reaction: H₂SO₄(aq) + 2KOH(aq) → K₂SO₄(aq) + 2H₂O(l)

Identify the spectator ion(s) in the following reaction: Zn(s) + Cu(NO₃) ₂(aq) → Cu(s) + Zn(NO₃) ₂(aq)

Which of the following is a balanced net ionic equation for the reaction between copper(II) chloride and zinc metal to form copper metal and zinc chloride?

When aqueous solutions of K₂CO₃ and CaCl₂ are mixed, what is the correct formula for the precipitate that forms?

When one compound is converted into two elements during a chemical reaction, a decomposition reaction has occurred.

Would an aqueous solution of CH₃OH contain ions? If so, indicate the formulas of the ions in the solution.

Would an aqueous solution of KOH contain ions? If so, indicate the formulas of the ions in the solution.

When acetylene gas, C₂H₂, burns in air, a combustion reaction occurs. Which of the following is a balanced equation that represents this reaction, which occurs when welding torches are used?

Would an aqueous solution of K₂SO₄ contain ions? If so, indicate the formulas of the ions in the solution.

Sterno, or "canned heat," contains methanol, CH₃OH, and is used for heating containers of food. Which of the following is a balanced equation that represents the combustion reaction that occurs when methanol burns in air?

When aqueous solutions of NaOH and MgCl₂ are mixed, a precipitate forms. What is the correct formula for the precipitate?

Which of the following is a balanced net ionic equation for the reaction between iron(II) chloride and potassium hydroxide to form iron(II) hydroxide and potassium chloride?

Identify the spectator ions in the following reaction: Zn(s) + 2HNO₃(aq) → Zn(NO₃) ₂(aq) + H₂(g)

Complete and balance the equation for the reaction that occurs when HBr(aq) and KOH(aq) are mixed.

Which of the following is a balanced net ionic equation for the reaction between hydrochloric acid and potassium hydroxid?

Quiz 5: Chemical Reactions and Equations

Complete and balance the equation for the reaction that occurs when H2SO4(aq) and NaOH(aq) are mixed.

When balancing a chemical equation, it is acceptable to change the subscripts on the formulas of the skeletal equation.

When powdered sulfur, S8, burns in air, a purple flame is produced, as well as a toxic, foul-smelling gas. What is the balanced equation for the reaction between sulfur and oxygen gas?

Complete and balance the equation for the reaction that occurs when HCl(aq) and Mg(OH) 2(aq) are mixed. This reaction occurs in your stomach if you take Milk of Magnesia®.

When writing an ionic equation, how would Mg(NO3) 2(aq) be represented?

Identify the spectator ions in the following reaction: H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(l)

Identify the spectator ion(s) in the following reaction: Zn(s) + Cu(NO3) 2(aq) → Cu(s) + Zn(NO3) 2(aq)

Which of the following is a balanced net ionic equation for the reaction between copper(II) chloride and zinc metal to form copper metal and zinc chloride?

When aqueous solutions of K2CO3 and CaCl2 are mixed, what is the correct formula for the precipitate that forms?

When one compound is converted into two elements during a chemical reaction, a decomposition reaction has occurred.

Would an aqueous solution of CH3OH contain ions? If so, indicate the formulas of the ions in the solution.

Would an aqueous solution of KOH contain ions? If so, indicate the formulas of the ions in the solution.

When acetylene gas, C2H2, burns in air, a combustion reaction occurs. Which of the following is a balanced equation that represents this reaction, which occurs when welding torches are used?

Would an aqueous solution of K2SO4 contain ions? If so, indicate the formulas of the ions in the solution.

Sterno, or "canned heat," contains methanol, CH3OH, and is used for heating containers of food. Which of the following is a balanced equation that represents the combustion reaction that occurs when methanol burns in air?

When aqueous solutions of NaOH and MgCl2 are mixed, a precipitate forms. What is the correct formula for the precipitate?

Which of the following is a balanced net ionic equation for the reaction between iron(II) chloride and potassium hydroxide to form iron(II) hydroxide and potassium chloride?

Identify the spectator ions in the following reaction: Zn(s) + 2HNO3(aq) → Zn(NO3) 2(aq) + H2(g)

Complete and balance the equation for the reaction that occurs when HBr(aq) and KOH(aq) are mixed.

Which of the following is a balanced net ionic equation for the reaction between hydrochloric acid and potassium hydroxid?

Complete and balance the equation for the reaction that occurs when H₂SO₄(aq) and NaOH(aq) are mixed.

When powdered sulfur, S₈, burns in air, a purple flame is produced, as well as a toxic, foul-smelling gas. What is the balanced equation for the reaction between sulfur and oxygen gas?

Complete and balance the equation for the reaction that occurs when HCl(aq) and Mg(OH) ₂(aq) are mixed. This reaction occurs in your stomach if you take Milk of Magnesia^®.

When writing an ionic equation, how would Mg(NO₃) ₂(aq) be represented?

Identify the spectator ions in the following reaction: H₂SO₄(aq) + 2KOH(aq) → K₂SO₄(aq) + 2H₂O(l)

Identify the spectator ion(s) in the following reaction: Zn(s) + Cu(NO₃) ₂(aq) → Cu(s) + Zn(NO₃) ₂(aq)

When aqueous solutions of K₂CO₃ and CaCl₂ are mixed, what is the correct formula for the precipitate that forms?

Would an aqueous solution of CH₃OH contain ions? If so, indicate the formulas of the ions in the solution.

When acetylene gas, C₂H₂, burns in air, a combustion reaction occurs. Which of the following is a balanced equation that represents this reaction, which occurs when welding torches are used?

Would an aqueous solution of K₂SO₄ contain ions? If so, indicate the formulas of the ions in the solution.

Sterno, or "canned heat," contains methanol, CH₃OH, and is used for heating containers of food. Which of the following is a balanced equation that represents the combustion reaction that occurs when methanol burns in air?

When aqueous solutions of NaOH and MgCl₂ are mixed, a precipitate forms. What is the correct formula for the precipitate?

Identify the spectator ions in the following reaction: Zn(s) + 2HNO₃(aq) → Zn(NO₃) ₂(aq) + H₂(g)