Question

Answer the following questions on the basis of given paragraph.

Osmotic pressure is widely used to determine molar masses of proteins and polymers. Two solution having same osmotic pressure are called isotonic solutions water can flow in or out from a substance depending on if it is in hypotonic or hypertonic solutions. The direction of the osmosis can be reversed if a pressure larger than osmotic pressure is applied on solution side

i) People taking lot of salt experience puffiness or swelling of the body due to

(1) Water retention in tissue cells and intercellular spaces because of osmosis.

(2) Water loss from the cells through skin tissues

(3) Capillary action of water through skin pores

(4) Excessive thirst and drinking more water.

(ii) The preservation of meat by salting and of fruits by adding sugar protects them from bacterial action because

(1) Bacteria die of eating sugar salt

(2) Due to osmosis bacteria lose water on salted meat or candid fruit and die.

(3) Due to osmosis bacteria gain water on salted meat or candid fruit and die.

(4) Bacteria get stuck to the salt and sugar layers and die.

(iii) Sea water is desalinated to get fresh water by which of the following methods?

(1) When pressure more than osmotic pressure is applied pure water is squeezed out of sea water by reverse osmosis.

(2) When excess pressure is applied on sea water pure water moves in by osmosis.

(3) Water moves out from sea water due to osmosis. (4) Salt is precipitated from sea water when kept undisturbed for some time.

(iv) Osmotic pressure is generally preferred for determining the molecular masses of protein because

(1) It is difficult to find out mole fraction of proteins for calculation by other methods.

(2) At elevated temperature the proteins are likely to decompose and osmotic pressure is measured around room temperature.

(3) The apparatus involved in finding out osmotic pressure is simpler than other methods.

(4) It is easy to boil or freeze a solution containing proteins.

• A. Water retention in tissue cells and intercellular spaces because of osmosis.
• A. When pressure more than osmotic pressure is applied pure water is squeezed out of sea water by reverse osmosis.
• B. Due to osmosis bacteria lose water on salted meat or candid fruit and die.
• B. At elevated temperature the proteins are likely to decompose and osmotic pressure is measured around room temperature.

Answer 1

Ans.

(i) (1)

Sol. Due to osmosis water moves into the tissues and

intercellular spaces causing retention of water.

(ii) (2)

Sol. The bacteria on salted meant or candid fruits loss water through osmosis shrink and die.

(iii) (1)

Sol. Reverse osmosis is used for desalination of sea water.

(iv) (2)

Sol. Osmotic pressure has an advantage over other methods since osmotic because is measure at room temperature and many proteins and polymer decompose on boiling.