Question 1

Which of the following is a chemical change that occurs during the process of frying breakfast eggs?

Accepted Answer

Cooking the eggs until the whites solidify

Question 2

Antifreeze boiling out of a radiator is an example of which type of change?

Accepted Answer

Physical change

Question 3

Which of the following is the correct balanced chemical equation for the reaction of hydrogen gas with oxygen gas to form water?

Accepted Answer

$$ \mathrm{2H_2 + O_2$ \rightarrow 2H_2O} $$

Question 4

When methane ($$ \mathrm{CH_4$} ) $$burns in oxygen, what are the products of the reaction?

Accepted Answer

$$ \mathrm{CO_2$} $$ and $$ \mathrm{H_2O} $$

Question 5

How many grams of oxygen are necessary to react completely with 7.80 moles of copper according to the reaction $$ \mathrm{2Cu + O_2$ \rightarrow 2CuO} $$?

Accepted Answer

124.8 g

Question 6

If 100 g of sodium is used in the reaction $$ \mathrm{2Na + 2H_2O \rightarrow 2NaOH + H_2$} $$, how many grams of hydrogen gas will be produced?

Accepted Answer

4.4 g

Question 7

What is the minimum mass of oxygen gas necessary to produce 200 g of sulfuric acid in the reaction $$ \mathrm{2SO_2 + O_2$ + 2H_2O \rightarrow 2H_2SO_4} $$?

Accepted Answer

32.0 g

Question 8

A student decomposes sodium chlorate to form oxygen gas. If 6.4 g of oxygen is produced, how many grams of sodium chlorate were decomposed? $$ \mathrm{2NaClO_3 \rightarrow 2NaCl + 3O_2} $$

Accepted Answer

21.4 g

Question 9

When 20 g of $$ \mathrm{NH_3$} $$ and 50 g of $$ \mathrm{O_2$} $$ are allowed to react according to $$ \mathrm{4NH_3 + 5O_2 \rightarrow 4NO + 6H_2O} $$, which is the limiting reagent?

Accepted Answer

$$ \mathrm{NH_3$} $$

Question 10

Which of the following reactions is a combustion reaction?

Accepted Answer

$$ \mathrm{CH_4$ + 2O_2 \rightarrow CO_2$ + 2H_2O} $$

Question 11

Hydrogen chloride gas can be prepared by the following reaction: $$ \mathrm{NaCl + H_2SO_4 \rightarrow $$NaHSO_4$$ + HCl} . If 5.00 g $$NaCl is reacted, what is the theoretical yield of HCl?

Accepted Answer

3.07 g

Question 12

Balance the following chemical equation: $$ \mathrm{$$KClO_3$$ \rightarrow KCl + O_2$} $$

Accepted Answer

$$ \mathrm{2KClO_3 \rightarrow 2KCl + 3O_2} $$

Question 13

In the reaction $$ \mathrm{$$FeCl_3$$ + 3NaOH \rightarrow Fe(OH)_3 + 3NaCl} $$, what is the percent yield if 3.0 g of $$ \mathrm{$$FeCl_3$$}  is $$reacted and 1.7 g of $$ \mathrm{Fe(OH)_3}  is $$collected?

Accepted Answer

56.7%

Question 14

Which of the following best describes the law of conservation of mass in a chemical reaction?

Accepted Answer

The total mass of reactants equals the total mass of products

Question 15

Which of the following is NOT a sign of a chemical reaction?

Accepted Answer

Change in state from solid to liquid

Question 16

A solution contains 2.00 mol KCl, 1.50 mol $$NaNO_3$$, and 2.56 mol NaCl. How many moles of chloride ions are present?

Accepted Answer

4.56 mol

Question 17

Which of the following equations represents a synthesis reaction?

Accepted Answer

$$ \mathrm{2H_2 + O_2$ \rightarrow 2H_2O} $$

Question 18

If 4.2 g of $$ \mathrm{$$FeCl_3$$}  is $$reacted with excess $$ \mathrm{NaOH} $$, what is the theoretical yield of $$ \mathrm{Fe(OH)_3} $$?

Accepted Answer

2.4 g

Question 19

Which of the following is a balanced equation for the reaction of sodium with water?

Accepted Answer

$$ \mathrm{2Na + 2H_2O \rightarrow 2NaOH + H_2$} $$

Chapter 7: Chemical Reactions and Chemical Quantities – Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard