Atomic Theory

The atomic number of Nitrogen is

Isotopes are atoms of the same element having...

Why was Democritus not taken seriously?

What is the relative charge on a proton?

What device was used to discover the electron?

Who proposed the model of the atom containing the nucleus?

Which particle has a mass close of that of a neutron?

The nucleus is composed of

What were the results of Rutherford's gold foil experiment?

Who is credited with the atomic theory?

Which is not part of Dalton's atomic thoery?

An atom has 20 protons and a mass number of 40. How many neutrons does it contain?

How many electrons are in the following?

How are number of neutrons calculated?

Atoms can be seen with a(n)

Who was the first person to suggest the idea of atoms?

What does 17 represent in Oxygen-17?

The atomic number is defined as

Who proposed this model known as the "Plum Pudding" model?

Which particle has the least mass?

Which particle has no charge and is found in the nucleus?

The mass number equals

An atom has 19 protons and 20 neutrons. What is the atomic number?

Isotopes are atoms of the same element having

The atomic number of Nitrogen is

Who is credited with discovering the electron?