Question

Suppose of hcl and of o2 are added to an empty flask. How much will be in the flask at equilibrium?A. None. B. Some, but less than 155. mmol, C. 155. mmol, D. More than 155. mmol

Answer 1

This is an incomplete question, here is a complete question.

Hydrogen chloride and oxygen react to form water and chlorine, like this:

$4HCI(g)+O_2(g)\rightarrow 2H_2(g)+2CI_2(g)$

Use this chemical equation to answer the questions in the table below.

Suppose 155. mmol of HCl and 38.8 mmol of O₂ are added to an empty flask. How much HCl will be in the flask at equilibrium?

(1) None.

(2) Some, but less than 155. mmol,

(3) 155. mmol,

(4) More than 155. mmol,

Answer : The correct option is, (1) None

Explanation :

The given balanced chemical reaction is:

$4HCI(g)+O_2(g)\rightarrow 2H_2(g)+2CI_2(g)$

From the balanced chemical reaction, we conclude that

As, 4 mmole of HCl react with 1 mmoles of $O_2$

So, 155. mmole of HCl react with $\frac{155.}{4}\times 1=38.75$ mmoles of $O_2$

That means, $O_2$ is excess reagent and $HCl$ is a limiting reagent. All the moles of HCl will consume.

Hence, the correct option is, None.