How will you test in the laboratory, whether the given sample of water is hard or soft? Name two salts which make the water hard.

Name two metals which are lighter than water.

Name two salt water ecosystem.

Taps water is an example of soft water or hard water.

How would you obtain clear water from a sample of muddy water ?

Water molecules is very polar. Polar end of molecule attracts opposite charges on another water molecules (acts like magnet). How will you explain this property of water with refrence to upward movement of water? Comment on the upward move-ment of water given the intermolecular hydrogen bonding in water.

Name atleat two metals which do not react with air, water and acids.

How would you confirm that a colourless liquid given to you is pure water ?