Question

Hydrogen combines with oxygen to form water. Water exists in:
(A) liquid
(B) solid
(C) gas
(D) plasma

Answer 1

The chemical name of Water is Hydrogen dioxide. It is a transparent, tasteless, and odourless inorganic compound which is the main part of the earth’s atmosphere. It is very vital for all the life systems that exist on this earth.

Complete answer:
The chemical formula of water is ${H_2}O$. One molecule of water has two atoms of hydrogen and one atom of oxygen. The nature of bonding in the water molecule is covalent bonding. An oxygen atom has $6$ electrons in its valence shell. It requires $2$ more electrons to complete its octet. These two electrons are shared by hydrogen via a single covalent bond between hydrogen and oxygen. The geometry or shape of a water molecule is bent with a bond angle of ${104.5^0}C$ between the atoms. The bent shape is due to the presence of two lone pairs on oxygen which causes the molecule to have a bent shape to minimize the repulsion. The bond length of $O - H$bond is $97.5\,pm$. Due to a higher electronegative nature of oxygen, the water molecule is polar in nature. In nature, water exists in three forms i.e. solid, liquid, and gas. In solid-state, it exists at ice at a temperature of ${0^0}C$or $273K$. Above that, it exists as liquid, and above ${100^0}C$ or $373K$ it exists as steam in its gaseous form. In solid-state, the structure of water is highly ordered but loose. Water exists in a liquid state due to hydrogen bonding.
Hence, we can say that water exists in solid, liquid, and gaseous state.

Therefore option (A), (B), and (C) is correct.
Note:
In comparison to other liquids the surface tensions, thermal conductivity, and specific heat of water are high. It is a universal solvent as most of the acids, salts, gasses dissolve in it. It is very essential in digestion and biological processes that happen in living organisms.