Atomic Structure

Question 1

Define the mass number of an atom.

Answer 1

The mass number is the sum of the number of protons and neutrons in the nucleus of an atom.

Question 2

What are isotopes?

Answer 2

Isotopes are atoms with the same atomic number but with different mass numbers.

Question 3

What are ions?

Answer 3

Ions are species in which the proton and electron number are not the same.

Question 4

Define the atomic number of an atom.

Answer 4

The atomic number is the number of protons in the nucleus of an atom.

Question 5

What are cations?

Answer 5

Ions with a positive charge.

Question 6

What is the relative atomic mass of an atom?

Answer 6

The ratio of the average mass of one atom of an element to 1/12 of the mass of an atom of carbon-12.

Question 7

What is the relative molecular mass of an atom?

Answer 7

The ratio of the average mass of one molecule of a compound to 1/12 of the mass of an atom of carbon-12.

Question 8

What are anions?

Answer 8

Ions with a negative charge.

Question 9

Give the charges of:

Proton, Neutron, Electron

Answer 9

Proton= +1 charge
Neutron= no charge 
Electron= -1 charge

Question 10

Give the mass of:

Proton, Neutron, Electron

Answer 10

Proton= 1 unit (approx)
Neutron= 1 unit (approx)
Electron= 1/1840 units (very tiny)