Take a bucket of water . Drop given articles in it . Make separate lists of the article which sink in the water and those that float on it :
( eraser , sharpner , pencil , spoon , compass , scale , rubber band )

Take a long rubber band and cut it at one point . At one of its ends tie a clean washed stone or a 50g weight as shown in figure Now hold the other end of the rubber band and make a mark there . Keep the stone hanging in air and measure the length of the rubber band from the stone to the mark made earlier . now take water in a pot and hold the rubber band at such a height that the stone sinks in it . again measure the length of the rubber band up to the mark . : What is observed ?:

Take a long rubber band and cut it at one point . At one of its ends tie a clean washed stone or a 50g weight as shown in figure Now hold the other end of the rubber band and make a mark there . Keep the stone hanging in air and measure the length of the rubber band from the stone to the mark made earlier . now take water in a pot and hold the rubber band at such a height that the stone sinks in it . again measure the length of the rubber band up to the mark . : What could be the reason for a shorter length of the rubber band in water ? :

Apparatus: Beakers. Chemicals: Samples of various metals , water. Procedure: Drop a piece of each of the metal in separate beakers filled with cold water. Which metal floats on water? Why?