How many grams of sodium iodide, NaI, must be used to produce 27.2 g of iodine, I2?

Answer 1

mole of I₂ = mass/MW = 27.2 / 253.8 = 0.107 mole of I₂

1 mole I₂ = 2 mol NaI

0.1071 x 2 = 0.2142 mol NaI

NaI = 149.8

149.8 x 0.2142 = 32.08g of NaI formed

Answer: 32.08g of NaI

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