Rani prepared an acidified K2Cr2O7 paper by putting a drop potassium

Question

Activity Steps:

Rani prepared an acidified K₂Cr₂O₇ paper by putting a drop potassium dichromate solution followed by a drop of dil. sulphuric acid on it.

Then she took a test tube and added 0.1 gm of Na₂SO₃, put dilute sulphuric acid 2-3 drops and simultaneously brought the acidified K₂Cr₂O₇ paper to the mouth of the test tube.

Q1. What is the colour of acidified K₂Cr₂O₇ paper ?

Q2. a) What happens when dil. H₂SO₄ is added to a test tube containing dry Na₂SO₃ salt.

       b) Write chemical equation for the reaction that took place between  Na₂SO₃ and H₂SO₄.

       c) Is this a redox reaction?

Q3. a) What is the colour change when acidified K₂Cr₂O₇ paper is brought near the mouth of the test tube in which Na₂SO₃ + dil. H₂SO₄ is taken.

       b) Write a chemical equation for the reaction that took place in step 2. 

       c) Is this a redox reaction?

chem XI Q8