A sulfate (or sulphate) is a compound in which the hydrogen of
sulfuric acid is replaced by a metal.
Let's start by noting the atomic weights for the elements related to your question:
We will then calculate the molecular mass for each of the sulfates,
and work out the proportion that the metal forms of the total. These
calculations assume that you are interested in anhydrous forms. If you
are interested in hydrated forms, let me know which hydrated forms you
wish me to use.
According to the Sargent-Welch website
the relevant formulae are:
magnesium sulfate: MgSO4.
iron sulfate: FeSO4
potassium sulfate: K2SO4
zinc sulfate: ZnSO4
manganese sulfate: MnSO4
Therefore, the proportion of magnesium in magnesium sulfate, weight for weight, is
24.3 / (24.3 + 32.1 + 64) = 20.2%
The proportion of iron in iron sulfate, weight for weight, is
55.8 / (55.8 + 32.1 + 64) = 36.7%
The proportion of potassium in potassium sulfate, weight for weight, is
(39.1 * 2) / ( (39.1 * 2) + 32.1 + 64) = 44.9%
The proportion of zinc in zinc sulfate, weight for weight is
65.4 / (65.4 + 32.1 + 64) = 40.5%
The proportion of manganese in manganese sulfate, weight for weight, is
54.9 / (54.9 + 32.1 + 64) = 36.4%
Please request clarification if this answer does not yet meet your needs.
Periodic Table - WebElements
(for the atomic weights)
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