chemistry structure of an atom

What is the nucleus of an atom?

The dense center of the atom containing protons and neutrons.

What is an electron?

A negatively charged particle that orbits the nucleus.

What is a proton?

A positively charged particle found in the nucleus.

What is a neutron?

A neutral particle found in the nucleus.

What is the atomic number?

The number of protons in an atom.

What is the mass number?

The total number of protons and neutrons in the nucleus.

What are isotopes?

Atoms of the same element with different numbers of neutrons.

What is electron configuration?

The arrangement of electrons in shells around the nucleus.

What are electron shells?

Energy levels where electrons are found around the nucleus.

Why are electrons attracted to the nucleus?

Because opposite charges attract (negative electrons to positive protons).

What determines the element of an atom?

The number of protons in the nucleus.

Where are protons located?

In the nucleus.

Where are electrons located?

In energy levels (shells) around the nucleus.

Why do isotopes have different masses?

They have different numbers of neutrons.

What is the relative charge of a proton?

+1

What is the relative charge of an electron?

–1

What is the relative charge of a neutron?

0