1)
Common salt= sodium, chlorine
Hydrated copper sulfate= copper, sulfur, water
Sulphuric acid=hydrogen, sulfur, oxygen
2)
Idfk
3)
a)Relative atomic mass is the average mass of an elements atoms(total number of protons and neutrons)
b)An isotope is a form of an element that has the same number of protons but different number of neutrons
c)idfk
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