Which one of the following statements about water is not true ?
Hydrogen bonds are present in liquid water.
Water has a high boiling point.
Water has a high heat of fusion.
Water is a non-polar molecule.
Answer is Wrong!
Answer is Right!
This question was previously asked in
UPSC NDA-2 – 2019
– The polarity and the presence of hydrogen atoms bonded to a highly electronegative oxygen atom enable hydrogen bonding between water molecules.
– Hydrogen bonding is responsible for many of water’s unusual properties, such as high boiling point, high heat of fusion, high specific heat capacity, and high surface tension.
– Statement B is true; water has an exceptionally high boiling point (100°C at 1 atm) compared to other molecules of similar size and molar mass without hydrogen bonding (e.g., H2S, which boils at -60°C).
– Statement C is true; water requires a significant amount of energy to melt (heat of fusion) due to the need to break hydrogen bonds holding the ice lattice together.