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115 grams of HF are used to make 6 liters of solution. What is the molarity of this solution?

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Answer:

molarity = 0.008842 mol/L

Step-by-step explanation:

To make an aqueous solution of HF, the concentration will be calculated by: concentration (c) (or molarity) = number of moles present (n) ÷ volume needed (V) (in litres)

since we don't have moles, we can calculate moles by:

number of moles (n) = mass present (m) (in grams) ÷ molar mass (M) (in grams per mole), which we can find using a standard IUPAC Periodic Table

∴ n(HF) = m/M = 115/(1.008 + 19.00) = 0.053053 mol

Now we have the number of moles present, we can calculate concentration:

∴ c(HF) = n/V = 0.053053/6L = 0.008842 mol/L

I have provided the answer in 4 significant figures, since the majority of the data used, that is, from the periodic table, is in 4 significant figures, but you can also do 3 significant figures since the mass of HF provided in the question is 3 significant figures.

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