is the smallest identifying particle of an element that has the properties of the element.

all of the following are subatomic particles except:

are found in the centre of the atom

the nucleus of the atom contains the

electrons are found at quite a distance from the nucleus in a series of levels known as

are positively charged

are negatively charged

have no charge

the size of the charge on a proton is equal to the size of the charge on the:

In atoms, the number of protons equal the number of the:

the mass of the proton is equal to the mass of the:

are responsible for the mass of the atom

are responsible for the volume of the atom:

the Atomic number is the number of:

the mass number of an element is the total number of:

Each electron shell can hold up to 2 electrons

shells closest to the nucleus fill up first.

are different atoms of the same element that have the same number of protons and electrons but different number of neutrons.

have the same atomic number but different mass number.

If the atom phosphorus has 15 protons, how many electrons does it have?

If the atom phosphorus has 15 protons, what is its atomic number?

If the atom phosphorus has 15 protons, and has a mass number of 31, how many neutrons does it have?

General idea about the structure of elements.

Ancient Greek who proposed the existence of atoms.

used radioactive particles to discover the structure of the atom.

based his atomic theory on experimentation.

sphere of negative charge

force holding protons and neutrons together.

small particles that may make up protons and neutrons.

forces between electrons and protons.

ATOMIC MASS NUMBER = PROTONS + NEUTRONS

ATOMIC NUMBER = PROTONS = NELECTRONS

NEUTRON NUMBER= MASS NUMBER - PROTON NUMBER

NEUTRON NUMBER= MASS NUMBER - ATOMIC NUMBER