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pickupchik [31]
4 years ago
12

What mass (in g) of NH3 must be dissolved in 475 g of methanol to make a 0.250 m solution?1.90 g4.94 g1.19 g2.02 g8.42 g

Chemistry
1 answer:
atroni [7]4 years ago
5 0

Answer:

2.02 g

Explanation:

Molality (m) is the <em>number of moles of solute dissolved in 1 kg (1000 g) of solvent- </em>that is,

molality = moles of solute ÷ mass of solvent (kg)

<em> </em>

Our first step is to calculate the moles of NH₃ in 475 grams of methanol, using <u>molality</u> as a conversion factor.

0.250 mol/kg × 0.475 kg = 0.119 mol

This solution contains <u>0.119 moles of NH₃</u>. Now we must convert the moles to grams, using the <u>molar mass of NH₃</u> as a conversion factor .

17.031 g/mol × 0.119 mol = 2.02 g

Therefore, 2.02 grams of NH₃ must be dissolved in 475 grams of methanol to make a 0.250 m solution.

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Answer:

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Explanation:

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