Consider a solution initially containing 0.300 mol of hydrogen fluoride (HF). How many grams of Naf (42.0 /mo vould...

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Answer 1

Answer #1

According to Henderson-Hasselbulch equation:

pH = pKa + Log(n_NaF/n_HF)

i.e. 3 = -Log(7.2*10^-4) + Log{(w/42)/0.3}

i.e. 3 = 3.14 + Log(w/12.6)

i.e. Log(12.6/w) = 0.14

i.e. 12.6/w = 1.38

Therefore, the mass of NaF needed = 12.6/1.38 = 9.128 g

Answer 2

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