Advertisements
Advertisements
प्रश्न
Give reasons: Lakes freeze from top towards bottom.
Advertisements
उत्तर
During winter, the temperature of lake water keeps on decreasing. Since cold water is heavier, it moves towards the bottom.
APPEARS IN
संबंधित प्रश्न
Among NH3, H2O and HF, which would you expect to have highest magnitude of hydrogen bonding and why?
Why is it said that-
Water is a universal solvent.
Why is it said that-
There is no alternative to water for cleaning purposes.
Sea water is a bad conductor of electricity.
Explain the various properties of water.
Why is the density of seawater more than that of rain water?
Why should a glass bottle completely filled with water never be kept in a freezer?
Define the following.
Freezing point
Some of the properties of water are described below. Which of them is/are not correct?
(i) Water is known to be a universal solvent.
(ii) Hydrogen bonding is present to a large extent in liquid water.
(iii) There is no hydrogen bonding in the frozen state of water.
(iv) Frozen water is heavier than liquid water.
If same mass of liquid water and a piece of ice is taken, then why is the density of ice less than that of liquid water?
Give reasons: Ice floats on water.
\[\ce{H2O2}\] is a better oxidising agent than water. Explain.
Why does water show high boiling point as compared to hydrogen sulphide? Give reasons for your answer.
Write two reactions to explain amphoteric nature of water.
The boiling point of water increases with ______ in pressure.
What are the physical properties of pure water?
The density of gold is 19 g/cm3. If 1.9 × 10−4 g of gold is dispersed in one litre of water to give a sol having spherical gold particles of radius 10 nm, the number of gold particles per mm3 of the sol will be ______ × 106.
