Atomic Structure Definitions

Question 1

Atomic number

Answer 1

The number of protons in the nucleus of an atom

Question 2

Mass number

Answer 2

The total number of protons and neutrons in the nucleus of an atom

Question 3

Relative atomic mass (RAM)

Answer 3

The average weighted mean mass of an atom of an element relative to one twelfth of the mass of an atom of carbon 12

Question 4

Relative isotopic mass (RIM)

Answer 4

The mass of an atom of an isotope of an element relative to one twelfth of the mass of an atom of carbon 12

Question 5

Isotopes

Answer 5

Atoms which have the Same atomic number but a different mass number (same amount of protons different amounts of neutrons)

Question 6

Relative molecular mass (RMM)

Answer 6

The average weighted mean mass of a molecule relative to one twelfth of the mass of an atom of carbon twelve

Question 7

Relative formula mass (RFM)

Answer 7

The average weighted mean mass of a species relative to one twelfth of an atom of carbon 12

Question 8

Molecular ion

Answer 8

An ion formed by the removal of an electron from a molecule

Question 9

First ionisation energy

Answer 9

The energy required to convert one mole of gaseous atoms into gaseous ions with a single positive charge

Question 10

Second ionisation energy

Answer 10

The energy required to convert one mole of gaseous ions with a single positive charge into gaseous ions with a double positive charge

Question 11

Third ionisation energy

Answer 11

The energy required to convert one mole of gaseous ions with a double positive charge into gaseous ions with a triple positive charge