Is Matter Around Us Pure? — Science STD 9 — Question

Give the formulae of the compounds formed from the following set of element:
Sodium and phosphorus.

Convert the temperature of 373°C to the Kelvin scale.

Name the process by which the various ‘dyes’ (coloured materials) present in black ink can be separated.

If the fish is being fried in a neighbouring home, we can smell it sitting in our own home. Name the process which brings this smell to us.

What is meant by saying that metals are malleable and ductile?

Out of a colloid, solution and a suspension:
Which one has the largest particles?

In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:

1. Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.
2. The Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion.
3. Assertion is true but the Reason is false.
4. The statement of the Assertion is false but the Reason is true.

Assertion: Medicine are easily absorbed by our body in colloidal form.
Reason: It is because they have large surface area and therefore, absorbed easily.

‘A substance has a definite shape as well as a definite volume’. Which physical state is represented by this statement?

Which subatomic particle is not present in an ordinary hydrogen atom?