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3 years ago

Calculate the grams of solute needed to prepare 107 mL of a 2.75 M magnesium

Chemistry

1 answer:

murzikaleks [220]3 years ago

8 0

Answer: 28.02 g

Explanation:

The M stands for molarity. It is moles of solute/liters of solution. We can use the molarity to convert liters to mL, then make a proportion to find the grams.

$\frac{2.75 mol}{L} *\frac{1L}{1000mL} =\frac{2.75 mol}{1000mL}$

Now that we have molarity in moles and mL, we can use the 107mL to get moles.

$\frac{2.75moles}{1000mL} *107mL=0.29425mol$

We would multiply moles by molar mass to get grams. The molar mass of magnesium chloride is 95.211 g/mol.

$0.29425mol*\frac{95.211g}{mol} =28.02g$

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