Chem 1 Review & Some

Front

What is the mass number of an element?

Back

The mass number is the total number of protons and neutrons in the nucleus of an atom.

Front

What subatomic particles are found in the nucleus of an atom?

Back

Protons and Neutrons.

Front

How do you calculate the number of neutrons in an atom?

Back

Subtract the atomic number (number of protons) from the mass number.

Front

What is half-life in radioactive decay?

Back

Half-life is the time required for half of the radioactive atoms in a sample to decay.

Front

If a substance has a half-life of 10 years, how much of a 100g sample remains after 20 years?

Back

25g remains after 20 years (2 half-lives).

Front

What particles are found in the cloud surrounding an atom's nucleus?

Back

Negatively charged electrons.

Front

What is the atomic number of an element?

Back

The atomic number is the number of protons in the nucleus of an atom.

Front

How many protons are in a bromine atom?

Back

Bromine has 35 protons.

Front

What is the charge of a neutron?

Back

Neutrons have no charge (they are neutral).

Front

What is the difference between an atom and an ion?

Back

An atom is neutral, while an ion has a net charge due to the loss or gain of electrons.