Carbon and its Compounds — Science STD 10 — Question

The modern periodic table was prepared by:

1. Dobereiner.
2. Newlands.
3. Bohr.
4. Mendeleev.

Which of the following is (are) true when HCl (g) is passed through water?

1. It does not ionise in the solution as it is a covalent compound.
2. It ionises in the solution.
3. It gives both hydrogen and hydroxyl ion in the solution.
4. It forms hydronium ion in the solution due to the combination of hydrogen ion with water molecule.

1. 1 only
2. 3 only
3. 2 and 4
4. 3 and 4

Which of the following can undergo a chemical reaction?

Solid calcium oxide reacts vigorously with water to form calcium hydroxide accompanied by liberation of heat. This process is called slaking of lime. Calcium hydroxide dissolves in water to form its solution called lime water. Which among the following is (are) true about slaking of lime and the solution formed?

1. It is an endothermic reaction.
2. It is an exothermic reaction.
3. The pH of the resulting solution will be more than seven.
4. The pH of the resulting solution will be less than seven.

1. 1 and 2
2. 2 and 3
3. 1 and 4
4. 3 and 4

What is the chemical name of a substance used in white washing?

-CHO represents the functional group:

An alloy is:

1. An element.
2. A compound.
3. A homogeneous mixture.
4. A heterogeneous mixture.

The functional group which always occurs in the middle of a carbon chain is:

1. Alcohol group.
2. Aldehyde group.
3. Carboxyl group.
4. Ketone group.