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What is the molality of a solution that contains 418.8 g HCl in 4.62 kg water?

Select one:
O a 2.49
Ob. 0.00249
Oc. 15.3
Od.4.19e5

User Pmn
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2 Answers

3 votes
the answer is a 2.49
User MShekow
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3 votes

Answer:

a 2.49

Step-by-step explanation:

Molality is a measure of concentration of solution which describes the number of moles of solute per kilograms of the solvent.

Molality (M) = number of moles of solute (n) / kg solvent

According to the question; mass of solute (HCl) = 418.8g, mass of solvent (water) = 4.62kg

To find the number of moles (n) of solute (HCl), we use; mass (g) / molar mass (g/mol)

Molar mass of HCl = 1 + 35.5 = 36.5g/mol

Hence, n= 418.8/36.5

n= 11.4739

n= 11.5

Therefore, Molality= 11.5 mol of HCl / 4.62kg of water

M= 11.5/4.62

M= 2.489

Hence, molality of the solution is 2.49

User Michael Niemand
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