Atomic Discovery & Structure

Front

What is the mass number of an isotope?

Back

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

Front

Who proposed the Planetary model of the atom?

Back

Niels Bohr proposed the Planetary model of the atom, which depicts electrons orbiting the nucleus like planets around the sun.

Front

In an atom, what does the number of protons equal?

Back

The number of protons in an atom is equal to the number of electrons.

Front

What is the mass number of copper-63?

Back

The mass number of copper-63 is 63 u.

Front

How many neutrons are in an oxygen atom?

Back

An oxygen atom has 8 neutrons.

Front

What is an atom?

Back

An atom is the smallest unit of matter that retains the properties of an element.

Front

What are protons?

Back

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

Front

What are neutrons?

Back

Neutrons are neutral particles found in the nucleus of an atom.

Front

What are electrons?

Back

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

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.