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3 years ago

10

Consider the reaction. PCl5(g)↽−−⇀PCl3(g)+Cl2(g) K=0.042 The concentrations of the products at equilibrium are [PCl3]=0.18 M and

[Cl2]=0.30 M . What is the concentration of the reactant, PCl5, at equilibrium?

1 answer:

tatyana61 [14]3 years ago

6 0

<u>Answer:</u> The equilibrium concentration of $PCl_5$ is 1.285 M.

<u>Explanation:</u>

The chemical equation for the decomposition of phosphorus pentachloride follows:

$PCl_5(g)\rightleftharpoons PCl_3(g)+Cl_2(g)$

The expression for equilibrium constant is given as:

$K_c=\frac{[PCl_3][Cl_2]}{[PCl_5]}$

We are given:

$K_c=0.042$

$[PCl_3]=0.18M$

$[Cl_2]=0.30M$

The concentration of solid substances are taken to be 1. Thus, they do not appear in the equilibrium constant expression.

Putting values in above equation, we get:

$0.042=\frac{0.18\times 0.30}{[PCl_5]}$

$[PCl_5]=1.285$

Hence, the equilibrium concentration of $PCl_5$ is 1.285 M.

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Answer:

A. 256

Explanation:

In a solution where a liquid is the sovent, we'll use the van't Hoff factor, which is the ratio between the number of moles of particles produced in solution and the number of moles of solute dissolved, will be equal to 1.

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ΔTemp.f = Temp.f° - Temp.f

where,

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Solving for the molality, b = ΔTemp.f/( i * Kf)

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Answer:

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Explanation:

Molecular formulas show correct and accurate number of each type of the atoms which are present in molecule.

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