H₂ = 2 g/mol
1 x 2 = 2 g of H₂
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K = 39.09 g/mol
2 x 39.09 = 78.18 g of K
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Mg = 24.3 g/mol
3 x 24.3 = 72.9 g of Mg
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He = 4 g/mol
4 x 4 = 16 g of He
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Order : K , Mg , He and H₂
hope this helps!
