Module 2A - Isotopes

Question 1

Define Isotopes

Answer 1

Atoms of the same element with a different number of neutrons.

Question 2

Which elemental isotope do we use as a standard?

Answer 2

Carbon - 12

Question 3

The symbol for relative atomic mass

Answer 3

Ar

Question 4

Define relative atomic mass

Answer 4

the weighted mean mass of an atom of an element compared to 1/12th of the mass of an atom of Carbon - 12

Question 5

How to work out relative atomic mass using percentage abundance

Answer 5

Multiply the Atomic mass of an element (e.g. (12) Carbon) by the percentage given (%), add them all together and divide by 100…

Question 6

Relative molecular mass

Answer 6

Mr, atomic masses from the periodic table. Add them all up. H2O = 1+1+16 = 18, Mr of H2O