Solution

C

Solution

i

Solution

i

Solution

iii

Solution

ii

Solution

i

Solution

Solution

Osmotic presuure=iCRT
where, C=concentration of solute in terms of Molarity)
R= Gas constant = 0.082 L(atm)(mol)⁻¹K⁻¹
T=temperature in Kelvin
i=Van't-Hoff factors=1 for non-electrolyte
5% urea solution means 5 g urea is present in 100ml of solution.
mole of urea=weight
given/Molecular weight of urea
5 g/60 g mol⁻¹= 1/12
Hence, Concentration of urea (in terms of Molarity) [C]
= (moles of urea(n) /volume of solution)×1000 ={(1/12)/100} × 1000 = 10/12
Hence Osmotic pressure=iCRT=1 × (10/12) × 0.082 × 300 atm
= 20.52 atm
or
Given,
The mass of water = 100 g
The mass of urea = 7.5 g
The mass of Z = 42.75 g
The molar mass of urea = 60 g/mol
Both the solutions have same freezing point
Since both the solutions have the same freezing point the change in freezing points (ΔT𝔣) for both the solutions is same.

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Solution

(a) We can observe the given graph and thus calculate the Half-life:
Concentration of reactant reduces from 0.8 to 0.4 in (20 – 10) = 10 seconds.
Again the concentration reduces to half (0.4 to 0.2) in (30 - 20) = 10 seconds.
Therefore we find that the half-life of reaction remains constant. Hence, order of reaction is one.

(b) No, due to exponential relation, the curve never touches the x-axis. hence it does not become zero.

Solution

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OR
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