Hydrogen Bonding & Water

The anomalous behavior of water is due to:

• ionic bonding
• van der Waals forces
• covalent bonding
• hydrogen bonding

Coastal area has moderate temperature than deserts because:

• Higher elevation in deserts
• Lack of vegetation in deserts
• Influence of nearby ocean or sea
• Presence of sand dunes

The presence of water in coastal areas maintains a moderate climate because of:

• high density of water

• high surface tension of water

• high latent heat of vaporization of water

• high specific heat capacity of water

H₂​O has a higher boiling point than HF because:

• HF molecules have stronger hydrogen bonds compared to water molecules.
• Water molecules have weaker intermolecular forces compared to hydrogen fluoride molecules.
• The boiling point of a substance is determined by its molecular weight, and HF has a higher molecular weight than H2O.
• Water molecules are held together by stronger hydrogen bonds compared to the hydrogen fluoride molecules.

High density of water is important for marine life because:

• The high density of water provides buoyancy and support for marine organisms.
• The high density of water helps marine organisms to swim faster.
• The high density of water provides protection against predators for marine organisms.
• The high density of water allows marine organisms to conserve energy while floating.

What is the benefit of high surface tension of water for insects:

• Allows insects to fly faster
• Enables insects to breathe underwater
• Helps insects camouflage in water
• Allows insects to walk on water without sinking

The high viscosity of water is important because:

• It allows substances to dissolve in it easily and helps in transporting nutrients and waste in living organisms.
• It reduces the surface tension of water and allows insects to walk on it.
• It increases the boiling point of water and helps in cooking food.
• It makes water less dense and allows objects to float in it.

Water has maximum density at:

• 0 degrees Celsius
• 20 degrees Celsius
• 10 degrees Celsius
• 4 degrees Celsius

Ice as compared with water is:

• less dense

• more dense

• equal dense

• not dense

When water cools down below 4^oC, it:

• evaporates

• compressed

• contracts

• expands