Kerala Board Solutions for Chapter: Chemical Changes, Exercise 8: Extended activities

Making a volcano
Heap up some ammonium dichromate powder on a tile. Deposit on it the chemical present on a match stick, and ignite. Write down the changes happening there.
Change in colour _____
Change in amount _____
Exchange of energy ____

Kindling fire by pouring oil.
Heap up some potassium permanganate on a tile. Keep a piece of dry cotton wick on top of it. Pour one or two drops of glycerine on the wick. Observe the changes.

Take a magnesium ribbon and clean it by scrubbing. Then burn it in air. Collect the product formed and dissolve it in water. Dip litmus papers and pH paper in this solution and observe. Find out the reason for the results of the observations.

Take sodium chloride solution in a beaker. Add to it a few drops of phenolphthalein. With the help of two carbon rods, let electricity pass through the solution. Record your observations. What is your inference? 

Take some silver nitrate solution in a test tube and add some sodium chloride solution to it. What is the colour of the precipitate formed? Filter the precipitate using a filter paper, place it on a watch glass and keep it exposed to sunlight. What do you observe? Try to write down the equation of your observation with the help of your teacher. Identify the change of energy involved in the second chemical reaction and write down what type of chemical reaction it is.