ATI - HESI Chemistry Practice Test 1

Question 1

If 0.5 moles of NaCl are dissolved in 2.0 liters of water, what is the molarity of the solution?

Accepted Answer

0.25 M

Answer

0.50 M

Answer

1.00 M

Answer

2.50 M

Question 2

Which type of chemical bond is formed when two nonmetal atoms share electrons equally?

Accepted Answer

Nonpolar covalent bond

Answer

Ionic bond

Answer

Polar covalent bond

Answer

Metallic bond

Question 3

How many valence electrons does an oxygen atom (atomic number 8) have?

Accepted Answer

6

Answer

2

Answer

4

Answer

8

Question 4

When hydrochloric acid (HCl) reacts with sodium hydroxide (NaOH) in a neutralization reaction, what are the products?

Accepted Answer

NaCl and H₂O

Answer

H₂ gas and NaCl

Answer

Na metal and HClO

Answer

NaOH and Cl₂

Question 5

Two atoms of the same element that have the same number of protons but different numbers of neutrons are called:

Accepted Answer

Isotopes

Answer

Ions

Answer

Allotropes

Answer

Isomers

Question 6

Which statement best describes an exothermic chemical reaction?

Accepted Answer

It releases heat energy to the surroundings.

Answer

It absorbs heat energy from the surroundings.

Answer

It requires a catalyst to release energy.

Answer

It only occurs at temperatures above 100 °C.