Differentiate between molarity and molality values for a solutio

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsLong Answer Type

261.

(a) Explain the following:

(i) Henry’s law about the dissolution of a gas in a liquid.

(ii) Boiling point elevation constant for a solvent.

(b) A solution of glycerol (C3H8O3) in water was prepared by dissolving some glycerol in 500 g of water. This solution has a boiling point of 100.42°C. What mass if glycerol was dissolved to make this solution? (Kb for water = 0.512 K kg mol-1)

1757 Views

262.

a) Calculate the freezing point of the solution when 1.9 g of MgCl2 (M = 95 g mol−1) was dissolved in 50 g of water, assuming MgCl2 undergoes complete ionization.
 (Kf for water = 1.86 K kg mol−1)

(b)
(i) Out of 1 M glucose and 2 M glucose, which one has a higher boiling point and why?
(ii) What happens when the external pressure applied becomes more than the osmotic pressure of solution?

OR

(a)When 2.56 g of sulphur was dissolved in 100 g of CS2, the freezing point lowered by 0.383 K. Calculate the formula of sulphur (Sx).
 
(Kf for CS2 = 3.83 K kg mol−1, Atomic mass of sulphur = 32 g mol−1]

(b)Blood cells are isotonic with 0.9% sodium chloride solution. What happens if we place blood cells in a solution containing
(i)1.2% sodium chloride solution?
(ii)0.4% sodium chloride solution?

4922 Views

 Multiple Choice QuestionsShort Answer Type

263.

(i) Gas (A) is more soluble in water than Gas (B) at the same temperature which one of two gases will the higher value of K(Henry's constant) and why ?

(ii)In non-ideal solution, what type of deviation shows the formation of maximum boiling azeotropes?

5632 Views

264.

Calculate the boiling point of the solution when 4g of MgSO4 (M =120 g mol-1) was dissolved in 100g of water,assuming MgSO4 undergoes complete ionization.

(Kb for water =0.52 K kg mol-1)

4146 Views

Advertisement
265.

What is meant by ‘reverse osmosis’?

1134 Views

Advertisement

266.

Differentiate between molarity and molality values for a solution. What is the effect of change in temperature on molarity and molality values?


Molarity is defined as the number of moles of solute dissolved per litre of solution.

 

Molality of a solution is defined as the number of moles of solute dissolved in 1000 grams of solvent.

 

While molarity decreases with an increase in temperature, molality is independent of temperature. This happens because molality involves mass, which does not change with a change in temperature, while molarity involves volume, which is temperature dependent.
1353 Views

Advertisement
267.

A solution prepared by dissolving 8.95 mg of a gene fragment in 35.0 mL of water has an osmotic pressure of 0.335 torr at 25°C.

Assuming that the gene fragment is a non-electrolyte, calculate its molar mass.

2469 Views

 Multiple Choice QuestionsLong Answer Type

268.

(a) Define the following terms :
(i) Molarity
(ii) Molal elevation constant (Kb)

(b) A solution containing 15 g urea (molar mass = 60 g mol–1) per litre of the solution in water has the same osmotic pressure (isotonic) as a solution of glucose (molar mass = 180 g mol–1) in water. Calculate the mass of glucose present in one litre of its solution.

OR

(a) What type of deviation is shown by a mixture of ethanol and acetone? Give reason.

(b) A solution of glucose (molar mass = 180 g mol–1) in water is labelled as 10% (by mass). What would be the molality and molarity of the solution?
(Density of solution = 1.2 g mL–1)

2099 Views

Advertisement

 Multiple Choice QuestionsShort Answer Type

269.

Define the following terms:
Colligative properties

1551 Views

270.

Define the following terms:
Molality (m)

1349 Views

Advertisement