Front

Who developed the planetary model of the atom?

Back

Niels Bohr

Front

What does the number 6 represent in the context of an element?

Back

Atomic number

Front

What is the correct symbol for a Bromine ion that gains 1 electron?

Back

Br^-1

Front

List the order of scientists related to atomic theory from earliest to most recent: Democritus, John Dalton, JJ Thomson, Ernest Rutherford.

Back

Democritus, John Dalton, JJ Thomson, Ernest Rutherford.

Front

How many protons does Argon have?

Back

18 protons

Front

What is the atomic mass of an element?

Back

The weighted average mass of an element's isotopes, measured in atomic mass units (amu).

Front

Define atomic number.

Back

The number of protons in the nucleus of an atom, which determines the element's identity.

Front

What is the charge of a Bromine ion that gains one electron?

Back

-1

Front

Who proposed the first modern atomic theory?

Back

John Dalton

Front

What is the significance of JJ Thomson's cathode ray experiment?

Back

It led to the discovery of the electron.