P-1 Periodic Classification of Element — Science STD 10 — Question

There is an oil layer on the water surface of river in your area. What will you do?

Write the chemical name and formula of:

1. Common salt, and
2. Caustic soda.

To which group in the periodic table does the element carbon belongs? Write down the electronic configuration of carbon and deduce the valency of carbon.

State any two uses of diamond.

Define boiling point of a liquid.

Name a device which helps to maintain potential difference across a conductor (say, a bulb).

Write the molecular formulae of the following compound.
Sodium aluminate

When you smell a favourite food your mouth begins to water (that is, you secrete saliva). Write down what the following are examples of:
The smell of the food.

Out of convex mirror and concave mirror, whose focus is situated behind the mirror?