Question

 Properties of Water

1. Describe how hydrogen bonding determines many properties of water.
2. List the properties of water that make it a valuable solvent, and distinguish between hydrophilic and hydrophobic substances.
3. Explain how the molarity of a solution—the number of moles of a solute per liter of solution—is used to measure the concentration of solutes in solution.
4. Discuss the properties of water that are critical for the survival of living organisms.

Answer 1

1. Hydrogen bonding in water is formed between Hydrogen and Oxygen which is already covalently bound to another Hydrogen.

Hydrogen bond gives the polar nature to the water.

Hydrogen bond is responsible for making water a polar molecule , for giving it high specific as well as latent heat. Water is also a universal solvent. Its high density and cohesive as well as adhesive properties make it a universal solvent.

2. Water is a universal solvent. It is polar in nature and thus can dissolve all polar substances in it and thus it is a universal solvent.

Hydrophilic substances are those substances which have the capacity to get dissolved in water.

Hydrophobic substances are those substances which do not dissolve in water.

3. Molarity of a solution is the number of moles dissolved in 1L of a solution.

More the number of moles more will be the molarity.

No. of moles= Given mass/ molar mass

Molarity= no. of moles in 1L.

4. Properties of water which are critical for survival of organisms are-

1. It is a universal solvent- It dissolves various substances in it.

2. It has high density.

3. The hydrogen bonds between water molecules absorb the heat when they break and release heat when they form, which minimizes temperature changes. Water helps maintain a moderate temperature of organisms and environments.

4. The low density is what allows icebergs to float and are the reason that only the top part of lakes are frozen.

5. The cohesive and adhesive property of water allow it to climb to much higher length in the plants.