Why mercury is used in barometer for measuring atmospheric pressure?

Why is mercury used in a barometer ?

What would be the height of column in barometer if water ("density" = 1000 Kg//m^(3)) is used instead of mercury for measuring atmospheric pressure?

Describe mercury barometer for measurement of atmospheric pressure. OR Describe Torricelli experiment for measurement of atmospheric pressure.

Why mercury is used in barometer instead of water ?

Why water is not used in barometers?

Explain why does the mercury level in a barometer go down when atmospheric pressure decreases?