Chemical Reactions and Equations — Science STD 10 — Question

Consider the structures of the three cyclic carbon compounds A, B and C given below and select the correct option from the following:

Which one of the following can be used as an acid–base indicator by a visually impared student?

1. Litmus.
2. Turmeric.
3. Vanilla essence.
4. Petunia leaves.

Which of the following is an endothermic process?

The process in which a carbonate ore is heated strongly in the absence of air to convert it into metal oxide is called:

Which of the following are present in a dilute aqueous solution of hydrochloric acid?

Reaction which has equal number of atoms of all the elements on both sides of a chemical equation is called

Select the incorrect statement.
a. The formula of the compound is calcium sulphate dihydrate.
b. When mixed with water and left for half an hour, this compound sets into a hard mass.
c. If heated at higher temperature, the compound becomes dehydrated and is called dead burnt plaster.
d. Both (a) and (b)

Match the following with the correct response:

Column A	Column B
(i) Addition reaction	(a) Hydrogenation
(ii) Substitution reaction	(b) Methanol
(iii) Denaturation	(c) Carbon tetrachloride
(iv) Esterification	(d) Ethyl ethanoate

The by product in soap industry is: