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·      WATER AS A MOLECULE - 

     Various uses and properties of water are manifestations of its chemical structure. In a water molecule, two hydrogen atoms are covalently linked to a oxygen atom. However, the sharing of electrons between oxygen and hydrogen atoms is unequal, they tend to be more closer towards oxygen atom than hydrogen. Because of this, hydrogen atoms develop a partial atom than hydrogen. Because of this, hydrogen atoms develop a partial positive charge (8) while that of oxygen has a partial negative charge (8). Thus, the water molecule is polar; contains two poles. The angle between the two 105⁰.hydrogen atoms with respect to oxygen atoms Electrostatic attraction between a positively charged region of one water molecule and a negatively charged region of an adjacent one is the force for the formation of hydrogen bonds. Each water molecule can form up to four hydrogen bonds with surrounding molecules. In Ice, hydrogen bonds are arranged tetrahedrally, so ice molecules form a regular tetrahedral [8:14 pm, 30/03/2022] Bareilly Tuitions: crystalline structure. Liquid water is thought to contain the same arrangement of molecules as in ice, except that in the former the bonds are more quickly broken and formed. Temperature affects the number of hydrogen bonds; with the increase in temperature the number of hydrogen bonds decreases. Hydrogen bonds are stronger than the vander waal's forces but weaker than covalent or ionic bonds. In fact, they can be formed between any two molecules where a hydrogen atom is bonded to a highly electronegative atom, particularly fluorine, oxygen of nitrogen. Hydrogen atom forms a kind of bridge between the two other atoms and hence the name hydrogen bond.