Question 1

Which of the following best describes a chemical change?

Accepted Answer

Iron rusting when exposed to air

Question 2

A student measures the mass of a sample as 12.30 g and its volume as 4.1 mL. What is the density of the sample, reported with the correct number of significant figures?

Accepted Answer

$3.0\ \mathrm{g/mL}$

Question 3

Which statement about the scientific method is correct?

Accepted Answer

Experiments are used to test hypotheses.

Question 4

Which of the following is a heterogeneous mixture?

Accepted Answer

Sand and iron filings

Question 5

Convert $2.5\ \mathrm{cm^3}$ to $\mathrm{mm^3}$.

Accepted Answer

$25000\ \mathrm{mm^3}$

Question 6

Which element is a noble gas?

Accepted Answer

Neon (Ne)

Question 7

Which of the following best explains why water boiling is an endothermic process?

Accepted Answer

Energy is absorbed to break intermolecular forces.

Question 8

What is the electron configuration for a neutral atom of magnesium ($\mathrm{Mg}$, atomic number 12)?

Accepted Answer

$1s^2\ 2s^2\ 2p^6\ 3s^2$

Question 9

Which of the following statements about isotopes is correct?

Accepted Answer

Isotopes have the same atomic number but different mass numbers.

Question 10

A compound contains 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass. What is its empirical formula?

Accepted Answer

$\mathrm{CH_2O}$

Question 11

Which of the following is a physical property?

Accepted Answer

Color

Question 12

What is the molar mass of $\mathrm{C_2H_6O}$ (ethanol)?

Accepted Answer

$46.07\ \mathrm{g/mol}$

Question 13

Which of the following best describes the periodic law?

Accepted Answer

Elements are arranged by increasing atomic number and show repeating properties.

Question 14

Which of the following ions is formed when sodium reacts according to the octet rule?

Accepted Answer

$\mathrm{Na^+}$

Question 15

A sample contains $3.01 	imes 10^{23}$ molecules of water. How many moles of water are present?

Accepted Answer

$0.500\ \mathrm{mol}$

Question 16

Which of the following best describes a transition metal?

Accepted Answer

An element with partially filled d sublevels

Question 17

Which of the following compounds is named correctly?

Accepted Answer

NaCl: sodium chloride

Question 18

Which of the following has the highest ionization energy?

Accepted Answer

Fluorine (F)

Question 19

A student needs to convert $5.0\ \mathrm{kg}$ to grams. What is the correct answer?

Accepted Answer

$5000\ \mathrm{g}$

Question 20

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

Accepted Answer

The total mass of reactants equals the total mass of products.

Introduction to Chemistry: Midterm Review Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards