Suggest a list of metals in the order in which they displace each other from the solution of their salts. Al, Cu, Fe, Mg and Zn.

Arrange the following metals in the order in which they displace each other from the solution of their salts. Al, Cu, Fe, Mg and Zn.

Give reasons : Al metal cannot be produced by the electrolysis of aqueous solution of Al salt.

Give reasons for the following. Copper cannot displace zinc from its salt solution.

A man sitting at a height of 20m in a tall tree on a small island in the middle of the river observes two poles directly opposite each other on the two banks of river and in line with the foot of the tree. If the angles of depression of the feet of the poles from a point at which the man is sitting on the three on either side of the river are 60° and 30° respectively. Find the width of the river.

Name two metals which will displace Hydrogen from dilute acids,and two metals which will not.

Two poles of equal heights are standing opposite to each other on either side of the road which is 80m wide. From a point between them on the road the angles of elevation of the top of the poles are 60° and 30° respectively. Find the height of the poles .

Two poles of equal heights are standing opposite each other on either side of the road,which is 80m wide.From a point between them on the road,the angles of elevation of the top of the poles are 60^@ and 30^@ respectively.Find the height of the poles and the distances of the point from the poles.

The poles of equal height are standing opposite to each other on either side of a road which is 100meters wide.From a point between them on the road,the angle of elevation of the tops are 30^@ and 60^@ .Find the position of the point and also the height of the poles.