ASN SR SEC SCHOOLCHEMISTRY ASSIGNMENT
CLASS XI
1) The thermochemical data for the formation of argonchloride (ArCl) are given below:
Ar(g)+1/2 Cl2 ArCl(g)
i)Enthalpy of dissociation of chlorine = -243kJ
ii)Electron gain enthalpy of chlorine= -348.3kJ
I iii)Ionisation enthalpy of argon=1526.3kJ
iv)Lattice enthalpy of argon chloride = -703kJ
Predict whether the formation of argon chloride is favourable or unfavourable?
2) With thehelp of M O theory explain the magnetic behavior of O2 2-.
3) At what temperature on Celsius scale will the volume of a given mass of a gas at 00c become half of its volume at constant pressure? (136.50c)
4) Calculate the density of ammonia at 300c and 5bar pressure? (R=0.083 bar dm3 mol-1 K-1) (3.37g/dm3)
5) A gaseous mixture containing 50g of dinitrogen and10g of dioxygen were enclosed In a vessel of 10L capacity at 270c.Calculate
a) The number of moles of each
b) The partial pressure of each gas
c) The total pressure of gaseous mixture
6) What is Boyle temperature?
7) Give two assumptions of kinetic theory of gases which does not hold good.
8) Give three differences between a real and ideal gas.
9) Critical temperature of NH3 and CO2 are 405.5K and 304.10K respectively .Which of these gases will liquefy first when you start from 500K to this temp.?
10) Name the intermolecular forces between
i)Cl 2 and CBr4
ii)SiH4 molecules
iii)He atoms in liquid HCl
iv)HCl molecules in liquid HCl
v)He and a polar molecule
vi)water molecule
11) Derive the relation between Cp and Cv.
12) The enthalphy of combustion of a substance A( l) at 298K and 1 atm pressure is
- 2546.0kJ/mol
What is ?U for the reation.
13) Explain why heat capacity is not a state function.
14)Enthalpies of formation of CO(g),CO2 (g),N2O4 (g) are -110,-393,81 and 9.7kJ/mol respectively.Calculate ?Hr for the reation
N2O4 (g)+3CO2 (g ) N2O(g)+3CO2(g)
15) In a reaction of equilibrium what will happen if
CO(g)+2H2 (g) CH3OH(g)
a)volume of reaction vessel in which reactant and product are contained ,is suddenly reduced to half
b)the partial pressure of hydrogen is suddenly doubled.
16)Which of the following can act as both Bronsted acid and base?
a)HCO3- b)O2- c)NH3 d)H2O
17) Write the formula of conjugate acid of
a)C6H5OH b)NH2NH2 c)HCO- 3
18) Calculate the pH of a solution of 0.001M solution of Ba(OH)2 assuming it to be completely ionized.
19) Calculate the pH of a solution formed by mixing 0.2M NH4Cl and 0.1M NH3.The pKb of ammonia is 4.75
20)The Ksp of CaF2 at 298K is 1.7x10-10 .Calculate its solubility in mol/L.