The main components of brass are:

1. Copper and tin
2. Copper and iron
3. Copper and lead
4. Copper and zinc

The drying agent used to dry Ammonia is:

1. Concentrated Sulphuric acid
2. Calcium oxide
3. Sulphurous acid
4. Calcium hydroxide

A few drops of universal indicator are added to colourless solution A, B, C and D with pH 2, 10, 9 and 7 respectively. Which of the following test tube is labelled with incorrect colour ?

Assertion (A): Hydrogen is a neutral gas but it cannot be dried by concentrated sulphuric acid.

Reason (R): The gas reacts with this acid.

1. Both A and R are true and R is the correct explanation of A.
2. Both A and R are true but R is not the correct explanation of A.
3. A is true but R is false.
4. A is false but R is true.