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3 years ago

Which aqueous solution of KI freezes at the lowest temperature?

Chemistry

1 answer:

slavikrds [6]3 years ago

3 0

Answer:

b. 2 mol of KI in 500. g of water

Explanation:

We have to apply the colligative property of freezing point depression.

The formula is: ΔT = Kf . m . i

As the (Kf . m . i) is higher, then the freezing temperature will be lower.

i refers to the Van't Hoff factor (number of ions dissolved in the solution)

KI → K⁺ + I⁻ (i =2)

Kf is constant so, we have to search for the highest m (molality)

Molality means the moles of solute in 1kg of solvent.

The highest m is option b → 2 mol of KI / 0.5 kg = 4 mol/kg

a. 1 mol of KI / 0.5 kg = 2 mol/kg

c. 1 mol of KI / 1kg = 1 mol/kg

d. 2 mol of KI / 1kg = 2 mol/kg

1000 g = 1kg. In order to determine molality we need to convert the mass (g) of solvent to kg

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A 52.0 mL portion of a 1.20 M solution is diluted to a total volume of 278 mL. A 139 mL portion of that solution is diluted by a

RoseWind [281]

Answer:

$C_3=0.125M$

Explanation:

Hello!

In this case, we can divide the problem in two steps:

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$V_1C_1=V_2C_2$

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3 years ago

NaOH(aq) is transferred into a test tube. CaCl2(aq) is added to the tube. What is the formula for the precipitate (if any) that

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Answer:

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