Question 1

Which law is demonstrated when the total mass of reactants equals the total mass of products in a chemical reaction?

Accepted Answer

Law of Conservation of Mass

Question 2

What is the correct balanced equation for the combustion of methane ($$CH_4) in $$oxygen?

Accepted Answer

$$CH_4 + 2O_2$$ \rightarrow $$CO_2 + 2H_2O$

Question 3

Which type of chemical reaction is represented by the equation $$2HgO(s) \rightarrow 2Hg(l) + O_2$(g)$$?

Accepted Answer

Decomposition reaction

Question 4

In the reaction $$Zn(s) + $$CuSO_4$$(aq) \rightarrow $$ZnSO_4$$(aq) + Cu(s)$$, what type of reaction is occurring?

Accepted Answer

Single-replacement reaction

Question 5

Which of the following is a correct skeleton equation for the reaction between sodium and water?

Accepted Answer

$$Na + H_2O \rightarrow NaOH + H_2$

Question 6

What is the main purpose of balancing a chemical equation?

Accepted Answer

To satisfy the law of conservation of mass

Question 7

Which symbol in a chemical equation indicates that a substance is dissolved in water?

Accepted Answer

$$(aq)$$

Question 8

A student mixes solutions of potassium iodide and lead(II) nitrate. A yellow precipitate forms. Which type of reaction is this?

Accepted Answer

Double-replacement reaction

Question 9

Which equation represents a combination reaction?

Accepted Answer

$$2Mg + O_2$ \rightarrow 2MgO$$

Question 10

In the reaction $$2Al + 3CuSO_4 \rightarrow Al_2$(SO_4$)_3 + 3Cu$$, which element is being replaced?

Accepted Answer

Copper

Question 11

What is the balanced equation for the reaction of aluminum with oxygen to form aluminum oxide?

Accepted Answer

$$4Al + 3O_2 \rightarrow 2Al_2O_3$$

Question 12

Which of the following is NOT a step in writing and balancing a chemical equation?

Accepted Answer

Change the subscripts to balance atoms

Question 13

A candle burns in air, producing carbon dioxide and water. What type of reaction is this?

Accepted Answer

Combustion reaction

Question 14

Which equation represents a double-replacement reaction?

Accepted Answer

$$NaCl + $$AgNO_3$$ \rightarrow $$NaNO_3$$ + AgCl$$

Question 15

Which of the following best describes a decomposition reaction?

Accepted Answer

A single compound breaks down into two or more simpler substances

Question 16

In the reaction $$2KBr(aq) + Cl_2$(g) \rightarrow 2KCl(aq) + Br_2$(l)$$, what is the role of chlorine?

Accepted Answer

It is a reactant and replaces bromine

Question 17

Which of the following reactions is an example of a real-world application of a double-replacement reaction?

Accepted Answer

Formation of a precipitate when mixing solutions of sodium chloride and silver nitrate

Question 18

What is the correct balanced equation for the decomposition of calcium carbonate?

Accepted Answer

$$CaCO_3$$ \rightarrow CaO + $$CO_2$$

Question 19

Which of the following is a sign that a chemical reaction has occurred?

Accepted Answer

All of the above

Chapter 11: Chemical Reactions – Study Notes

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