Question

How many moles of potassium chlorate is to be heated to produce 11.2 litre oxygen?
(a) 1/2 mole
(b) 1/3 mole
(c) 1/4 mole
(d) 2/3 mole
​

Answer 1

option b 1/3 moles

hope this helps mate

Answer 2

To Find

How many moles of potassium chlorate is to be heated to produce 11.2 litre oxygen

Solution

We know that

At NTP (Normal Temp. & Pressure)

22.4 L of oxygen = 1 mole

Given that

11.2 L of oxygen

Mathematically

$\sf 22.4 \ L \longrightarrow 1 \ mole$

$\sf 11.2 \ L \longrightarrow "x" \ moles$

Calculating

Moles of oxygen (x)

By cross multiplication

We get

$\sf \longrightarrow x= \dfrac{11.2}{22.4}=\dfrac{1}{2} \ moles$

Therefore

11.2 L of oxygen = 0.5 moles

Chemical equation

$\sf 2KClO_{3} \xrightarrow{\Delta} 2KCl+3O_{2}$

From the chemical equation

We can understand that

2 moles of potassium chlorate on heating gives 3 moles of oxygen

According to the question

We are asked to find how many moles of potassium chlorate is to be heated to produce 11.2 litre oxygen

We found out that

11.2 L of oxygen = 0.5 mole

Mathematically

$\sf 3 \ moles \ of \ O_{2} \longrightarrow 2 \ moles \ of \ KClO_{3}$

$\sf 0.5 \ moles \ of \ O_{2} \longrightarrow "y" \ moles \ of \ KClO_{3}$

Calculating

Moles of potassium chlorate (y)

By cross multiplication

We get

$\sf \longrightarrow y= 0.5 \times \dfrac{2}{3} = \dfrac{1}{3} \ moles$

Therefore

1/3 moles of  potassium chlorate is to be heated to produce 11.2 L of oxygen

Hence

Option (b) is correct