Atomic Theory and Atomic Structure

Front

What is the main idea of John Dalton's atomic theory?

Back

Atoms are tiny, invisible particles; atoms of one element are all the same; atoms of different elements are different; compounds form by combining atoms.

Front

What subatomic particle did J.J. Thomson discover?

Back

Electrons.

Front

Which model of the atom was proposed by J.J. Thomson?

Back

Plum pudding model.

Front

What did Niels Bohr prove about electrons?

Back

Electrons are in energy levels.

Front

How do you calculate the mass number of an atom?

Back

Mass number = number of protons + number of neutrons.

Front

If an atom has 10 protons and 15 neutrons, what is its mass number?

Back

25.

Front

What are protons?

Back

Positively charged subatomic particles found in the nucleus of an atom.

Front

What are neutrons?

Back

Neutral subatomic particles found in the nucleus of an atom.

Front

What are electrons?

Back

Negatively charged subatomic particles that orbit the nucleus of an atom.

Front

What is the nucleus of an atom?

Back

The central part of an atom, containing protons and neutrons.