Question

16. Students perform the following steps in sequence: He takes a magnesium ribbon and rubs it with a sand paper.
He next puts in a boiling tube, that is filled with water and inverts another test tube on it, he worms the lower
test tube over the flame of a burning burner. Answer the followings
Why did he need to rub the magnesium ribbon before performing the activity.
Why did he need to heat the lower test tube
Which gas is involved and how could he test it?
. Give the chemical equation of the chemical reaction.​

Answer 1

1.He rubs Magnesium to Sand Paper in order to remove any oxide layer of MgO formed with reaction with atmospheric O2.

2.He is warming the lower because contents are in it,maybe to boil the water to produce steam because Mg tends to react with steam and shows almost no reaction with cold water

3.Gas is hydrogen.

4.Mg +H2O--------->MgO + H2,where Mg and MgO are solids while others are in gaseous state.