Q2 Exam Review - 8th 2024-25

Front

What is an atom?

Back

An atom is the smallest unit of matter that retains the properties of an element. It consists of a nucleus made of protons and neutrons, surrounded by electrons in an electron cloud.

Front

How many electrons are in a neutral atom?

Back

In a neutral atom, the number of electrons is equal to the number of protons.

Front

What is a compound?

Back

A compound is a substance formed when two or more different elements are chemically bonded together. For example, water (H2O) is a compound made of hydrogen and oxygen.

Front

What are subatomic particles?

Back

Subatomic particles are the particles that make up an atom. The main subatomic particles are protons, neutrons, and electrons.

Front

What charge do protons have?

Back

Protons have a positive charge.

Front

What charge do electrons have?

Back

Electrons have a negative charge.

Front

What charge do neutrons have?

Back

Neutrons have no charge (they are neutral).

Front

Where is most of an atom's mass located?

Back

Most of an atom's mass is located in the nucleus, which contains protons and neutrons.

Front

What is the electron cloud?

Back

The electron cloud is the region around the nucleus of an atom where electrons are likely to be found.

Front

What is the nucleus of an atom?

Back

The nucleus is the central part of an atom, containing protons and neutrons, and it holds most of the atom's mass.