Q: How many atoms are in $2.00\ \mathrm{mol}$ of sodium ($\mathrm{Na}$)? (Avogadro's number $= 6.022 \times 10^{23}\ \mathrm{atoms/mol}$)

$1.20 \times 10^{24}\ \mathrm{atoms}$

Question 1

A sample contains 18.0 grams of water ($\mathrm{H_2O}$). How many moles of water are present in the sample? (Molar mass of $\mathrm{H_2O}$ is $18.0\ \mathrm{g/mol}$)

Accepted Answer

$1.0\ \mathrm{mol}$

Question 2

How many atoms are in $2.00\ \mathrm{mol}$ of sodium ($\mathrm{Na}$)? (Avogadro's number $= 6.022 	imes 10^{23}\ \mathrm{atoms/mol}$)

Accepted Answer

$1.20 	imes 10^{24}\ \mathrm{atoms}$

Question 3

Which of the following best describes a redox reaction?

Accepted Answer

A reaction in which electrons are transferred between species

Question 4

What is the oxidation number of sulfur in $\mathrm{SO_2}$?

Accepted Answer

$+4$

Question 5

Balance the following equation: $\mathrm{C_2H_6} + \mathrm{O_2} \rightarrow \mathrm{CO_2} + \mathrm{H_2O}$

Accepted Answer

$2\ \mathrm{C_2H_6} + 7\ \mathrm{O_2} \rightarrow 4\ \mathrm{CO_2} + 6\ \mathrm{H_2O}$

Question 6

Which of the following compounds is most likely to be insoluble in water?

Accepted Answer

$\mathrm{AgCl}$

Question 7

A solution is made by dissolving $5.85\ \mathrm{g}$ of sodium chloride ($\mathrm{NaCl}$) in water to make $0.100\ \mathrm{L}$ of solution. What is the molarity of the solution? (Molar mass of $\mathrm{NaCl}$ is $58.5\ \mathrm{g/mol}$)

Accepted Answer

$1.00\ \mathrm{M}$

Question 8

Which of the following is the correct formula for calcium phosphate?

Accepted Answer

$\mathrm{Ca_3(PO_4)_2}$

Question 9

Which of the following best describes a double replacement reaction?

Accepted Answer

Two compounds exchange ions to form two new compounds

Question 10

What is the limiting reactant when $2.0\ \mathrm{mol}$ of $\mathrm{H_2}$ reacts with $1.0\ \mathrm{mol}$ of $\mathrm{O_2}$ to form water according to $2\ \mathrm{H_2} + \mathrm{O_2} \rightarrow 2\ \mathrm{H_2O}$?

Accepted Answer

$\mathrm{H_2}$

Question 11

Which of the following is a decomposition reaction?

Accepted Answer

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

Question 12

Which of the following is the correct name for $\mathrm{H_2SO_4}$?

Accepted Answer

Sulfuric acid

Question 13

What is the empirical formula of a compound that contains $40.0\%$ carbon, $6.7\%$ hydrogen, and $53.3\%$ oxygen by mass?

Accepted Answer

$\mathrm{CH_2O}$

Question 14

Which of the following is a strong electrolyte in aqueous solution?

Accepted Answer

$\mathrm{NaCl}$

Question 15

Which of the following ions is polyatomic?

Accepted Answer

$\mathrm{NO_3^-}$

Question 16

Which of the following is a type II metal ion?

Accepted Answer

$\mathrm{Fe^{2+}}$

Question 17

What is the formula mass of $\mathrm{CaCO_3}$? (Atomic masses: $\mathrm{Ca} = 40.1$, $\mathrm{C} = 12.0$, $\mathrm{O} = 16.0$)

Accepted Answer

$100.1$

Question 18

Which of the following best describes what is reduced in a redox reaction?

Accepted Answer

The species that gains electrons

Question 19

Which of the following is the correct formula for the compound formed between aluminum and sulfate?

Accepted Answer

$\mathrm{Al_2(SO_4)_3}$

Introduction to Chemistry: Study Guide for Chapters 5–8 (Atoms, Moles, Chemical Reactions, and Redox)

Study Guide - Practice Questions

Study Guide - Flashcards