Question 1

Which of the following statements best describes a scientific hypothesis?

Accepted Answer

A hypothesis is a tentative explanation that is testable and falsifiable.

Question 2

Which of the following is an example of a chemical property?

Accepted Answer

Iron rusts when exposed to oxygen.

Question 3

A sample of matter is uniform throughout and can be separated into two or more substances by physical means. Which type of matter is this?

Accepted Answer

Homogeneous mixture

Question 4

Which of the following best illustrates the Law of Definite Proportions?

Accepted Answer

Water from any source always contains hydrogen and oxygen in a $$2:1$$ ratio by atoms.

Question 5

Which of the following changes is a chemical change?

Accepted Answer

A piece of wood burning in a campfire.

Question 6

A student measures the mass of a sample as $$2.340 g. $$How many significant figures are in this measurement?

Accepted Answer

4

Question 7

Which of the following best describes an isotope?

Accepted Answer

Atoms of the same element with different numbers of neutrons.

Question 8

How many protons and neutrons are in the isotope $$^{37}_{17}\mathrm{Cl}$$?

Accepted Answer

17 protons, 20 neutrons

Question 9

Which of the following ions is a cation?

Accepted Answer

$$\mathrm{Na}^+$$

Question 10

What is the correct name for the compound $$\mathrm{Co(NO_3$)_2}$$?

Accepted Answer

Cobalt(II) nitrate

Question 11

Which of the following best describes a crystalline solid?

Accepted Answer

A solid with particles arranged in a regular, repeating pattern.

Question 12

Which of the following is the correct formula for hydrogen sulfate?

Accepted Answer

$$\mathrm{HSO}_4^-$$

Question 13

A student adds $$2.341 	imes 376 	imes 0.007 on $$their calculator and gets $$6.15412. $$How many significant figures should the answer have?

Accepted Answer

1

Question 14

Which of the following best describes a physical change?

Accepted Answer

Water freezing to form ice.

Question 15

Which of the following is the correct name for $$\mathrm{Sr(NO_3$)_2}$$?

Accepted Answer

Strontium nitrate

Question 16

Which of the following is a polyatomic ion?

Accepted Answer

$$\mathrm{CO}_3$$^{2-}$$

Question 17

A compound contains $$40.0\%$$ carbon, $$6.7\%$$ hydrogen, and $$53.3\%$$ oxygen by mass. Which law does this illustrate?

Accepted Answer

Law of Definite Proportions

Question 18

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

Accepted Answer

$$\mathrm{CaCO}_3$$

Question 19

Which of the following best describes a scientific law?

Accepted Answer

A concise statement that summarizes a broad variety of observations and experiments.

Question 20

If an atom has 15 protons, 16 neutrons, and 18 electrons, what is its charge?

Accepted Answer

$$3^-$$

Foundations of General Chemistry: Matter, Measurement, and Atomic Structure

Study Guide - Practice Questions