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3 years ago

How many liters of water are needed to make a 4.00 M solution using 75.0

Chemistry

1 answer:

timurjin [86]3 years ago

7 0

Answer:

0.22L

Explanation:

Given parameters:

Concentration of solution = 4.00M

Mass of lithium Bromide = 75g

Unknown:

Volume of water = ?

Solution:

Concentration in terms of the molarity is the number of moles of solute in a solution.

Molarity = $\frac{number of moles }{volume of solution}$

let us find the number of moles first;

Number of moles = $\frac{mass}{molar mass}$

Molar mass of LiBr = 7 + 80 = 78g/mol

number of moles = $\frac{75}{78}$

number of moles = 0.96moles

Volume of water = $\frac{number of moles }{molarity}$ = 0.96/4 = 0.22L

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