Question 1

Which of the following statements best describes an atom?

Accepted Answer

An atom is the smallest particle of an element that retains the properties of that element.

Question 2

A neutral atom of sodium (Na) has an atomic number of 11 and an atomic mass of 23. How many neutrons does it have?

Accepted Answer

12

Question 3

Which of the following best explains why water (H$$_2O) is $$considered a polar molecule?

Accepted Answer

Oxygen has a stronger pull on electrons than hydrogen, resulting in an uneven distribution of charge.

Question 4

Which type of bond is responsible for holding two water molecules together?

Accepted Answer

Hydrogen bond

Question 5

If an atom has 8 electrons, how are they distributed in its energy levels?

Accepted Answer

2 in the first level, 6 in the second level

Question 6

Which of the following is a correct example of an ionic bond?

Accepted Answer

Na$$^+ + Cl$^-$$ → NaCl

Question 7

Which property of water allows it to absorb large amounts of heat before changing temperature?

Accepted Answer

High specific heat capacity

Question 8

A solution is made by dissolving 10 g of salt in 100 mL of water. In this solution, what is the solvent?

Accepted Answer

Water

Question 9

Which of the following best describes an isotope?

Accepted Answer

Atoms of the same element with different numbers of neutrons

Question 10

A chemical equation is written as: 6CO$$_2 + 6H$_2O$$ → C$$_6H$_{12}O$_6 + 6O$_2. $$How many oxygen atoms are present among the reactants?

Accepted Answer

18

Question 11

Which of the following statements about ions is correct?

Accepted Answer

Ions are formed when atoms gain or lose electrons.

Question 12

Which of the following best explains why water forms a meniscus in a graduated cylinder?

Accepted Answer

Adhesion between water molecules and the glass

Question 13

A solution has a pH of 3.0. Which of the following best describes this solution?

Accepted Answer

It is acidic and has a high concentration of H$$^+$$ ions.

Question 14

Which of the following is a property of water that is essential for life and is due to hydrogen bonding?

Accepted Answer

Cohesion

Question 15

Which of the following best describes a covalent bond?

Accepted Answer

A bond formed when two atoms share electrons

Question 16

Which of the following is true about the atomic number of an element?

Accepted Answer

It is equal to the number of protons in the nucleus.

Question 17

Which of the following is a real-life example of evaporative cooling due to water's properties?

Accepted Answer

Sweating in humans

Question 18

Which of the following best describes a molecule?

Accepted Answer

A group of atoms held together by covalent bonds

Question 19

If a neutral atom of chlorine (Cl) gains one electron, what is the resulting charge and why?

Accepted Answer

The atom becomes a Cl$$^-$$ ion because it has more electrons than protons.

Question 20

Which of the following is NOT a property of water that results from hydrogen bonding?

Accepted Answer

Low boiling point

Basic Chemistry Concepts for GOB Chemistry

Study Guide - Practice Questions