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Question
Calculate the mole ratio of 240 g of calcium and 240 g of magnesium. (Ca = 40 u ; Mg = 24 u)
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Solution
Mass of calcium = 240g
Molar mass of calcium = 40g
Number of moles in 40g of calcium = 1 mole
Therefore, number of moles in 240g of calcium = 240 / 40 = 6 moles
Mass of magnesium = 240g
Molar mass of magnesium = 24g
Number of moles in 24g of magnesium = 1 mole
Therefore, number of moles in 240g of magnesium = 240 / 24 = 10 moles
Therefore, mole ratio of 240g of calcium to 240g of magnesium is 3:5.
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