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What is the molality of a solution made by dissolving 5.2 g of NaCl in 100 g of water?

User Alagris
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Answer:

The molality is 0,89

Step-by-step explanation:

A molal solution indicates the moles of solute in 1 kg of solvent (1000 g). First, we calculate the weight of 1 mol of NaCl:

Weight NaCl= Weight Na + Weight Cl=23g + 35,5 g=58,5 g/mol

58,5 g----1 mol NaCl

5,2 g----x=(5,2 gx1 mol NaCl)/58,5 g=0,089 mol NaCl

100g water-----0,089 mol NaCl

1000g water----x=(1000g waterx0,089 mol NaCl)/100 g water

x=0,89 mol NaCl----> 0,89 m

User Juanma Feliu
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