Atomic Theory

Front

What is the Plum Pudding Model of the atom?

Back

A model proposed by J.J. Thomson where electrons are scattered within a ball of positive charge.

Front

What is the atomic number of an element?

Back

The number of protons in every atom of that element.

Front

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

Back

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

Front

What is the Quantum Mechanical Model of the atom?

Back

A model that describes electrons in terms of probabilities and wave functions, rather than fixed orbits.

Front

What does the term 'isotope' mean?

Back

Atoms of the same element that have the same number of protons but different numbers of neutrons.

Front

What is the significance of the nucleus in an atom?

Back

The nucleus contains protons and neutrons and is the center of the atom, holding most of its mass.

Front

What is the charge of an electron?

Back

Electrons have a negative charge.

Front

What is the charge of a proton?

Back

Protons have a positive charge.

Front

What is the charge of a neutron?

Back

Neutrons have no charge (they are neutral).

Front

What is the difference between atomic mass and atomic number?

Back

Atomic mass is the weighted average mass of an element's isotopes, while atomic number is the number of protons.