Chemistry Semster 1, 1-3 review questions

Front

What is a physical change?

Back

A physical change is a change that affects one or more physical properties of a substance without altering its chemical composition. Examples include freezing, melting, and dissolving.

Front

What is a chemical change?

Back

A chemical change is a change that results in the formation of new chemical substances. It involves a chemical reaction and changes the molecular structure of the substance.

Front

What is an example of a physical change?

Back

Freezing juice is an example of a physical change.

Front

Which of the following is NOT a physical change?

Back

Rust is not a physical change; it is a chemical change.

Front

What are neutrons?

Back

Neutrons are subatomic particles found in the nucleus of an atom that have no charge (neutral).

Front

What is the atomic number?

Back

The atomic number is the number of protons in the nucleus of an atom, which determines the element's identity.

Front

What is the atomic number of Lithium?

Back

The atomic number of Lithium is 3.

Front

What is the atomic number of Oxygen?

Back

The atomic number of Oxygen is 8.

Front

What are protons?

Back

Protons are positively charged subatomic particles found in the nucleus of an atom.

Front

What are electrons?

Back

Electrons are negatively charged subatomic particles that orbit the nucleus of an atom.