SSLC (English Medium) Class 9 - Tamil Nadu Board of Secondary Education Question Bank Solutions

Two immiscible liquids are taken in the above funnel for separation.
Which is denser, X or Y? Suggest any one example for X and one for Y. A third liquid Z which is soluble only in Y is added to the mixture, and the contents in the funnel are shaken well. How many layers will you observe now? How will you separate the three liquids? The boiling point of X is 98°C, that of Y is 43°C and that of Z is 75°C.

Which of the following non-metals can form alloys with metals?

The mixture of metal with mercury is called ______.

Elements are placed in periods based on the number of ______ in their atoms.

List the advantages of alloys.

Explain water of crystallization.

The number of water molecules present in one molecule of copper sulphate is ______.

The molecular formula of copper sulphate pentahydrate is ______.

Salts containing water of crystallization are called ______ salts.

Salts that do not contain water of crystallization are called ______.

What is the water of crystallization?

The burning of PVC releases ______.

Which among the following plastics release antimony when we reuse.

List the three unsafe plastics.

Why? do we remove plastics safely? How can it be done?

Mention two reasons for the harmful nature of plastics.

Write a note on Natural dyes.

The dye that can only be used on cotton is ______.

Dyes are aromatic compounds that originated from plants and insects.

The dye should be fast to light.