Use your brain power! Can you tell :
Light a bunsen burner. Open and close air hole at the bottom of the burner by means of the movable ring around it . When do you get yellow sooty flame? When do you get blue flame?

Use your brain power! Can you tell : Structural formulae of some monomers are given below. Write the structural formula of the homopolymer formed from them.

Use your brain power What do you mean by homologous chromosomes?

Use your brain power! Can you tell : Explain why does the lime water turns milky in the reaction of acetic acid with sodium carbonate.

Use your brain power! Can you tell : Write down structural formulae of the first four members of the various homologous series formed by making use of the functional groups.

Use your brain power! Can you tell : Explain by writing a reaction , which product will be formed on heating n-butyl alcohol with concentrated sulphuric acid.

Use your brain power! Can you tell : The names of four fatty acids separated from vegetable oils are given in the table. Identify the number of carbon - carbon double bonds from their structure and molecular formula from the below fatty acids which one when reacts with iodine will make the colour of iodine disappear.

Use your brain power! Can you tell : Draw three structural formulae having molecular formula C5H12. Give the names n-pentane, i-pentane and neo-pentane to the above structural formulae.

Use your brain power Sometimes, you may notice a black powder or white discs floating on the pickle or murabba, when a jar is opened after a long time. What exactly is this? Why are such food items not good to eat?

Apparatus: Bars of stainless steel, aluminium and copper, a candle, a burner, pins, etc. : Procedure: Take stainless steel (or iron), copper and aluminium bars, each about 30 cm long and having the same shape. Apply wax spots with the help of candle at a distance of 2 cm from each other on all the three bars. Stick a pin in each of these spots so that it is upright. Now insert the ends of all three bars into a flame at the same time. for a while. What do you see? From which bar do the pins start falling first? Why?