2 years ago

What is the molality of a solution that contains 109 grams of NaOH dissolved in 4.55kg of water? The molar mass of NaOH is 40.00

1 answer:

8 0

$C_{m}=\frac{n}{V}=\frac{m_{s}}{MV}\\\\
d=\frac{m}{V} \ \ \ \Rightarrow \ \ \ V=\frac{m}{d}=\frac{4550g}{1\frac{g}{cm^{3}}}=4550cm^{3}=4,55L\\\\
C_{m}=\frac{109g}{40\frac{g}{mol}*4,55L}\approx0,6M$

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