You visited us 1 times! Enjoying our articles? Unlock Full Access!

Byju's Answer

Standard XII

Chemistry

Real Gases

In an experim...

Question

In an experiment, $10$ L of air (containing $O_{3}$ ) at $1$ atm and $27^{o} C$ was passed through an alkaline KI solution. After neutralisation, free iodine requires $1.5$ mL of $0.01 N N a_{2} S_{2} O_{3}$ solution. The molar percentage of $O_{3}$ in air is $y \times 10^{- 4}$ . Here $y$ is (in nearest integer) :

Open in App

Solution

Moles of ozone $=$ Moles of iodine $= 2$ moles of $N a_{2} S_{2} O_{3}$
Moles of $N a_{2} S_{2} O_{3} = 1.5 \times 10^{- 3} \times 0.01 = 1.5 \times 10^{- 5}$
This is equal to the number of moles of ozone.
$22.4$ L of a gas at STP corresponds to $1$ mole.

Hence, the number of moles in $10$ L of air $= \frac{10}{22.4} = 0.4464$ moles

Mole percentage of ozone $= \frac{2 \times 1.5 \times 10^{- 5}}{0.4464} \times 100 = 0.00336$ $= 6.16 \times 10^{- 4}$

Suggest Corrections

Similar questions

Q. Ozone is estimated in air by passing certain volume of air through an acidified or neutral or basic

K I

solution when

O_{2}

is evolved and

I^{⊝}

is oxidised to

I_{2}

. Free

I_{2}

evolved is titrated with standard

N a_{2} S_{2} O_{3}

solution. In an experiment,

10

L of air at

1

atm and

27^{o} C

was passed through an alkaline

K I

solution and

I_{2}

liberated required

2

mL of

\frac{M}{800}

N a_{2} S_{2} O_{3}

solution. The volume percentage of

O_{3}

in sample is :

Q. For estimating ozone in the air, a certain volume of air is passed through an acidified potassium iodide solution. Oxygen is evolved and iodide is then oxidized to give iodine. When such a solution is acidified, free iodine is evolved which can be titrated with standard sodium thio-sulphate solution. In an experiment

10 l i t r e

of air at

1

atm and

27^{o} C

were passed through an alkaline

K I

solution, at the end, the iodine entrapped in the solution on titration as above required

1.5 l i t r e

0.01 N N a_{2} S_{2} O_{3}

solution. Calculate volume percent of

0. 3

in sample.

Q. 10 g of bleaching powder is dissolved in water containing some

{C H}_{3} C O O H

and diluted to 1 L. 20 ml of this solution on reaction with

K I

required 20 ml of 0.1

N {N a}_{2} S_{2} O_{3}

solution. Calculate percentage of available chlorine in it.

8.7

g of pyrolusite (impure

M n O_{2}

) was heated with conc.

H C l

. The

C l_{2}

gas evolved was passed through excess of

K I

solution. The iodine gas evolved required

80

ml of

\frac{N}{10}

hypo solution. The percentage of

M n O_{2}

in pyrolusite will be :

One litre of a mixture of

O_{2}

and

O_{3}

N T P

was allowed to react with an excess of an acidified solution of

K I

. The iodine liberated required

40

mL of

\frac{M}{10}

sodium thiosulphate solution for titration. Ultraviolet radiation of wavelength

300

nm can decompose ozone. Assuming that one photon can decompose one ozone molecule.

What is the total amount of

O_{2}

and

O_{3}

present in

1 ℓ

of the mixture at STP?

Join BYJU'S Learning Program

In an experiment, 10 L of air (containing O3) at 1 atm and 27oC was passed through an alkaline KI solution. After neutralisation, free iodine requires 1.5 mL of 0.01NNa2S2O3 solution. The molar percentage of O3 in air is y×10−4. Here y is (in nearest integer) :