Isotopes

Question 1

What is an isotope?

Answer 1

The same element with the same number of protons but different number of neutrons.
Same atomic number
Different mass number

Question 2

What is a nuclides?

Answer 2

A type of isotope

This refers to a specific nucleus that contains a certain number of protons and neutrons.

Question 3

What is the Relative Atomic Mass (RAM) (Ar)

Answer 3

Average mass of all the isotopes

The biggest number in a element is the RAM

Question 4

How do you work out the RAM?

Answer 4

Total mass of atoms / Total number of atoms

Mass of atoms = weight x percentage
Number of atoms = 100

Question 5

Example of RAM

Chlorine naturally exist as 2 isotopes 35/37 CL (chlorine 35) and 35/17 CL (chlorine 37). the abundance of chlorine -35 is 75% and the abundance of chlorine -37 is 25%.

Answer 5

(35 x 75) + (37 x 25)
(75 + 25)

2625 + 1925
100.

3550
100

= 35.5 (to 1dp)
Closer to 35 because chlorine -35 isotope is much more abundant than the chlorine -37 isotope.