Question

Let's have some chemistry :D

You are given 2 bottles. One contains $\sf Dil.{H}_{2}{SO}_{4}$ and the other contains $\sf Conc.{H}_{2}{SO}_{4}$
How will you identify which bottle is $\sf Dil.{H}_{2}{SO}_{4}$ and which one is $\sf Conc.{H}_{2}{SO}_{4}$
• Quality Answers :)​

Answer 1

In The Case of Dilute Sulphuric acid :-

Needed elements :- Zinc , Dil. Sulphuric acid .

When Diluted Sulphuric acid reacts with zinc , then it produces Zinc Sulphate and Hydrogen gas ( with a pop - up sound ) as products .

For the equation of this reaction kindly see the 1st attachment .

In The Case of Concentrated Sulphuric Acid :-

Needed Elements :- Zinc , Conc. Sulphuric acid .

When Sulphuric acid ( concentrated ) reacts with Zinc , then it produces Sulphur di - oxide gas which can turn acidified Potassium Dichromate Paper to green colour .

For the equation of this reaction kindly see the 2nd attachment .

Thus , With these observations we can easily distinguish that in which bottle Dil. Sulphuric acid is present and in which conc. Sulphuric acid is present i.e :-

If In any bottle , The present sulphuric acid reacts with zinc to produce sulphur dioxide gas , Then it is Concentrated Sulphuric Acid .

If In any bottle , The present sulphuric acid reacts with zinc to produce Zinc Sulphate and Hydrogen gas but not sulphur dioxide gas , Then it is Diluted Sulphuric Acid .

Hence , We are done !

Answer 2

Answer:

Aim: To differentiate between dil. H2SO4

and conc. H2SO4

Apparatus Used:-

Zinc granules(contains copper impurity to speed up the reaction), dil and conc. H2SO4

Procedure:

Observation:

• When we combine zinc granules with dil H2SO4 hydrogen gas is liberated and H2(hydrogen) gas is liberated along with a salt zinc sulphate(ZnSO4) is formed.
• When we combine zinc granules with conc. H2SO4 sulphur dioxide (SO2) is liberated and ZnSO4 (zinc sulphate) and water is formed.

Result:-

By the products dil H2SO4 and conc. H2SO4 are differentiated.

Note: The main difference between both the acids is that dil H2SO4 is not a good oxidising agent and thereby H2 gas is liberated but conc. H2SO4 is a strong oxidising agent,so H2 is oxidized to H2O hence we can easily differentiate between the two.

• For the reactions refer to the attachments.