Question

1. Differentiate between an atom and a molecule.
2. Why does the cut surface of brinjal turn brown?
3. What is valency? Give the valencies of the following: oxygen‚hydrogen‚sodium‚magnesium and chlorine.​

Answer 1

Explanation:

1 )Atoms are single neutral particles. Molecules are neutral particles made of two or more atoms bonded together.

2 ) When fresh fruits and vegetables are peeled or cut open, the enzyme called polyphenol oxidase (also called tyrosinase) contained in the cells is exposed to and reacts with the oxygen in the air. The reaction that occurs, which is called oxidation, is what turns the fruits and vegetables brown.

3) Sodium (Na) : 1. Magnesium (Mg) : 2. Chlorine (Cl)