Question

Find the total percentage of magnesium in magnesium nitrate crystals, Mg(NO3)2.6H2O
[Mg = 24; N = 14; O = 16 and H = 1]

August 4, 2024

Answer

Molecular weight of Mg(NO₃)₂.6H₂O

= 24 + 2[14 + 3(16)] + 6[2(1) + 16]

= 24 + 2[14 + 48] + 6[18]

= 24 + 2(62) + 108

= 24 + 124 + 108

= 256 g

256 g of magnesium nitrate crystals contains 24 g of magnesium

∴ 100 g of magnesium nitrate crystals will contain = $24\over 256$ × 100

= 9.375% = 9.38%

Hence, the percentage of magnesium in magnesium nitrate crystals is 9.38%

💡 Some Related Questions

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