Chemistry : Part I for Class XII
Solutions - 01

Instructions

1. All questions are compulsary.
2. Please give the explanation for the answer where applicable.
3. To view the answer, click on the Answer link alongside the Question.
* You can view the answer when the link becomesGreen Red. on completion of allocated time.


Q.1) The vapour pressure of benzene at certain temperature is 640mm Hg. To 39.08 of benzene, non-volatile and non-electrolyte solid-weighing 2.175g was added. The vapour pressure of solution was 600mm of Hg. Find the mass of the solute? (3 Marks) 

Q.2) The osmotic pressure of human blood is 7.65 atm at 37°C. For injecting glucose solution it is necessary the glucose solution has same osmotic pressure as of human blood. Find the molarity of glucose solution having same osmotic pressure as of human blood. (2 Marks) 

Q.3) An aqueous solution of a non-volatile and non-electrolyte substance boils at 100.5°C. Calculate osmotic pressure of this solution at 27°C. Kb (for water) per 1000g = 0.50. (3 Marks) 

Q.4) A decimolar solution of NaCl exerts osmotic pressure of 4.6 atm at 300K. Find the degree of dissolution.  (3 Marks) 

Q.5) Define-
(i) Mole fraction 
(ii) Molality  (2 Marks) 

Q.6) Which is better method for expressing concentration of solution – Molarity or Molality? (2 Marks) 

Q.7) What are colligative properties? Name them. (2 Marks) 

Q.8) Define binary solution? (1 Marks) 

Q.9) What is molarity? (1 Marks) 

Q.10) What do you understand by saying that molality of a solution is 0.2? (1 Marks)