Question

list the following from greatest to least mass: 1 mol of H2, 2 moles of K, 3 moles of Mg, and 4 moles of He

Answer 1

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!