Properties of water

• Hydrogen bonding of water molecules:

  • Water molecules attract each other due to their polarity
  • The plus end of one water molecule (a hydrogen atom) associates with the minus end of another water molecule (an oxygen atom)
  • Water molecules are also attracted to other polar molecules and ions
  • Hydrophilic substances interact with and dissolve in water, while hydrophobic substances like oils and fats do not interact well with water
• Density of water:

  • Density of water is the weight of the water per its unit volume
  • Density of water depends on the temperature of the water
  • The usual value used in calculations is 1 gram per milliliter (1 g/ml) or 1 gram per cubic centimeter (1 g/cm3)
• Ice floats in water because it is less dense than liquid water

  • Water expands when it freezes due to the hydrogen bonds forming a crystal lattice structure, causing the molecules to move further apart