Question

The relative atomic mass of chlorine is 35.5.
When calculating relative atomic mass, which particle is the mass of a chlorine atom compared
to?
A a neutron
B a proton
C an atom of carbon-12
D an atom of hydrogen-1

Answer 1

Explanation:

The A r values also allow you to work out that three oxygen atoms have the same mass as two magnesium atoms. Chlorine's A r of 35.5 is an average of the masses of the different isotopes of chlorine.

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A r values of elements.