Question

Why is water liquid at room temperature?

Answer 1

Hint: In case of water molecules, hydrogen bonding is involved. A hydrogen bond in water occurs between the hydrogen atom of one water molecule and the lone pair of electrons on an oxygen atom of a neighbouring water molecule.
Complete answer: water is a liquid at room temperature because of its tiny weak hydrogen bonding. This hydrogen bonding holds billions of water molecules together for small fractions of second. This sticky nature of water molecules is called its cohesion property. When water molecules stick to some other molecule then it is called adhesion property of water.
The hydrogen bonding of water molecules is the reason that allows polar compounds to dissolve rapidly in water. Polar compounds replace the energetically favourable water – water interactions with even more favourable water – solute interactions. On the other hand, non-polar compounds interfere with the favourable water – water interactions and tend to cluster together. This is why non-polar compounds are poorly soluble in water.
Polar substances that dissolve in water are said to be hydrophilic where ‘hydro’ means water and ‘philic’ means loving. Non-polar substances that do not dissolve in water and get separated from it are called hydrophobic where ‘phobic’ means fearing.
Water is a colourless, tasteless and odourless liquid at room temperature. It has a very high latent heat of fusion or melting.

Note:
Water can take many forms of matter. It is most common in its liquid phase. This liquid phase is generally meant by the word ‘water’. Water is a good conductor of heat but a poor conductor of electricity. It is also an excellent solvent.