Module 2-Foundations in chemistry

Question 1

Definition of relative ISOTOPIC mass

Answer 1

mass of an atom of an isotope compared to 1/12th of the mass of carbon 12

Question 2

Definition of relative ATOMIC mass

Answer 2

weighted mean mass of an atom of an element compared to 1/12th of the mass of carbon 12.

Question 3

How do you calculate relative atomic mass of an element using the abundances of its isotopes? (%)

Answer 3

1) List all isotopes of the element shown by the graph next to the % of which they make up.
2) Multiply the % by the isotope number for each isotope of the element.
3) Add up all the numbers and divide the total by 100. Leave answer to one decimal place or 3 significant figures.