Invert the following chemical terms into their definitions: Protons, Density, Atoms, Molecules and identify the number of electrons for neutral atoms with 12 protons and the name of the horizontal row

Here are the solutions to the questions:

SECTION A

QUESTION 1

1.1. If an atom has 12 protons in the nucleus, then it must have .......... to be neutral.
An atom is neutral when the number of protons (positive charge) equals the number of electrons (negative charge).

• C. 12 electrons around nucleus

1.2. Atoms consist of.........
Atoms are composed of subatomic particles: protons, neutrons, and electrons.

• C. Protons, electrons and neutrons

1.3. What are the horizontal rows on the periodic table called?
The horizontal rows on the periodic table are known as periods.

• D. periods

QUESTION 2

Match the term in Column A with the correct statement in Column B.

2.1. Density
Density is defined as mass per unit volume.

• C. Mass per unit volume

2.2. Molecules
A molecule is formed when two or more atoms are chemically bonded together.

• A. Two or more atoms chemically bonded

2.3. Protons
Protons are sub-atomic particles found in the nucleus that carry a positive charge.

• D. Positively charged sub-atomic particle