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1 year ago

What is the molality of 30g of NACI dissolved in 350g of water

Chemistry

2 answers:

ivolga24 [154]1 year ago

8 0

Answer:

1.47 m

Explanation:

The molality can be found using the following equation:

Molality = moles solute / mass (kg) solvent

In this case, NaCl is the solute and H₂O is the solvent. To find the molality, you need to (1) convert grams NaCl to moles (via the molar mass), then (2) convert grams H₂O to kilograms, and then (3) calculate the molality.

(Step 1)

Molar Mass (NaCl): 22.990 g/mol + 35.453 g/mol

Molar Mass (NaCl): 58.443 g/mol

30 grams NaCl 1 mole
-------------------------- x ------------------------ = 0.513 moles NaCl
58.443 grams

(Step 2)

1,000 grams = 1 kg

350 grams H₂O 1 kg
-------------------------- x ----------------------- = 0.35 kg H₂O
1,000 grams

(Step 3)

Molality = moles solute / mass (kg) solvent

Molality = 0.513 moles NaCl / 0.35 kg H₂O

Molality = 1.47 m

Anastasy [175]1 year ago

5 0

Answer:

1.45 mol/kg

Explanation:

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Answer:

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Explanation:

From the question given above, the following data were obtained:

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Specific heat capacity (C) =?

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Initial temperature (T1) = 10 °C

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