Define a solution. Give an example of $(i)$ gas in liquid solution $(ii)$ gas in gas solution.

How will you separate a mixture of common salt,camphor,and iron filings? Describe the process.

What is chromatography? Mention its applications.

Which of the following statements are true for pure substances?
$(i)$ Pure substances contain only one kind of particles.
$(ii)$ Pure substances may be compounds or mixtures.
$(iii)$ Pure substances have the same composition throughout.
$(iv)$ Pure substances can be exemplified by all elements other than nickel.

On heating,calcium carbonate gets converted into calcium oxide and carbon dioxide.
$(a)$ Is this a physical or a chemical change?
$(b)$ Can you prepare one acidic and one basic solution by using the products formed in the above process? If so,write the chemical equations involved.

State whether the following statement is true or false:
Non-metals are lustrous and good conductors of heat and electricity.