1C) Atomic structure

Question 1

isotopes

Answer 1

same element but have different atomic mass (same number of protons but different number of neutrons)

Question 2

RAM

Answer 2

relative atomic mass
(% of mass no.) + (% of mass no.) +…./100.
e.g. boron contains 20% 10^B and 80% 11^B. what is RAM?
(20 x 10) + (80 x 11) / 100