100+ Chemistry Questions and Answers for Competitive Exams - 1

Question: 1

Explain the terms, concrete and mortar?

A mixture of Cement, sand gravel (crushed stones) and water is called concrete.

A mixture of cement and sand in the ratio 3:1 with required amount of water is called mortar.

Question: 2

Mention the uses of sodium carbonate?

Sodium carbonate is used in the manufacture of paper, soap, textiles, paints etc.

In laundry and domestic purpose as a cleaning agent.

As lab reagent in qualitative and quantitative analysis.

In softening of hard water.

Question: 3

Mention the uses of bleaching powder?

It is used to bleach cotton and wood pulp.

It is used as disinfectant and germicide.

It is used as an oxidising agent in chemical industries.

Question: 4

What is annealing of glass?

The process of slow and uniform cooling is called annealing. It takes several days for completion.

Question: 5

How is pyrex glass manufactured?

Pyrex glass is manufactured by fusing a mixture of sodium carbonate, potassium carbonate, calcium carbonate, silica and borax.

It is used for making oven ware, flasks, beakers etc.

It is also used for making injection ampoules.