The particles present in strong electrolytes are

1. only molecules
2. mainly ions
3. ions and molecules
4. only atoms

In the following reaction, alkaline KMnO₄ adds oxygen to the ethanol and converts ethanol to an acid.

CH₃CH₂OH $\xrightarrow{\text{KMnO}_4}$ CH₃COOH

Which of the following is correct?

P. Alkaline KMnO₄ acts as reducing agent.

Q. Alkaline KMnO₄ acts as an oxidising agent.

1. Only P
2. Only Q
3. Both P and Q
4. Neither P nor Q

In an exothermic process, energy is released in the form of heat or light.

Which of the following could be exothermic processes?

P. Sublimation of camphor crystals

Q. Reaction of water with quick lime

R. Dilution of an acid

1. Only P
2. Only Q
3. Only R
4. Both Q and R

Percentage of calcium in calcium carbonate (CaCO₃) is

1. 40
2. 30
3. 48
4. 36