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3 years ago

7

How many grams of lithium sulfide must be dissolved in 1600.0 g water to make a 2.0 molal solution?

1 answer:

klasskru [66]3 years ago

7 0

Molality is the number of moles of solutes in 1 kg of solvent.
the molality of solution to be prepared is 2.0 molal.
therefore 2 moles in 1 kg water.
the mass of Li₂S required is - 46 g/mol x 2.0 mol = 92 g
the mass in 1 kg of solvent is - 92 g
Therefore mass of Li₂S required in 1600.0 g is - 92 g/kg x 1.6 kg = 147.2 g

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At 500 K the reaction 2 NO(g) + Cl2(g) ⇌ 2 NOCl(g) has Kp = 51 In an equilibrium mixture at 500 K, the partial pressure of NO is

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Answer:

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2 years ago

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miv72 [106K]

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3 years ago

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Ganezh [65]

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