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3 years ago

Calculate the molality of 75.0 grams of MgCl2 (molar mass=95.21 g/mol) dissolved in 500.0 g of solvent.

Chemistry

2 answers:

nordsb [41]3 years ago

5 0

<u>Answer:</u> The molality of magnesium chloride is 1.58 m

<u>Explanation:</u>

To calculate the molality of solution, we use the equation:

$\text{Molality}=\frac{m_{solute}\times 1000}{M_{solute}\times W_{solvent}\text{ (in grams)}}$

Where,

$m_{solute}$ = Given mass of solute (magnesium chloride) = 75.0

$M_{solute}$ = Molar mass of solute (magnesium chloride) = 95.21 g/mol

$W_{solvent}$ = Mass of solvent = 500.0 g

Putting values in above equation, we get:

$\text{Molality of }MgCl_2=\frac{75.0\times 1000}{95.21\times 500.0}\\\\\text{Molality of }MgCl_2=1.58m$

Hence, the molality of magnesium chloride is 1.58 m

Arada [10]3 years ago

4 0

Answer: C) 1.58 m

The molar mass of MgCl2 = 95.2g/mol.

UsaTestPrep

75.0g

95.2

mol

= 0.788mol

Explanation:

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If we repeat part A for an initial temperature of 273 K and final temperature of 1073 K.

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