ASSIGNMENT FOR CHAPTER 5 & 6 CLASS XI
1.The enthalpy of combustion of methane, graphite and dihydrogen at 298K are -890.3 KJ/mole, -393.5 KJ/mole, and -285.8 KJ/mole, respectively. Find the enthalpy of formation of methane.
2. The ejection of the photoelectrons from the silver metal in the photoelectric effect experiment can be stopped by applying the voltage of 0.35eV when the radiation 256.7 nm is used. Calculate the work function for silver metal.
3.In a compound C,H and N are present in ratio 9:1:3.5 by weight. Molecular mass of the compound is 108.Find out its molecular formula?
4.Explain Andrew’s Experiment for Liquifaction of gases? What is the significance of critical temperature?
ASSIGNMENT FOR CHAPTER 5 & 6 CLASS XIi
1.The enthalpy of combustion of methane, graphite and dihydrogen at 298K are -890.3 KJ/mole, -393.5 KJ/mole, and -285.8 KJ/mole, respectively. Find the enthalpy of formation of methane.
2. The ejection of the photoelectrons from the silver metal in the photoelectric effect experiment can be stopped by applying the voltage of 0.35eV when the radiation 256.7 nm is used. Calculate the work function for silver metal.
3.In a compound C,H and N are present in ratio 9:1:3.5 by weight. Molecular mass of the compound is 108.Find out its molecular formula?
4.Explain Andrew’s Experiment for Liquifaction of gases? What is the significance of critical temperature?
5. a) What is the effect of temperature on viscosity and surface tension of
a liquid?
b) Calculate the average kinetic energy of 32g of methane at 27°C
[ R=8.314J/K/mol ]
c) What will be the minimum pressure
required to compress 500 dm3 of air at 1 bar to 200 dm3
at 30°C? ASSIGNMENT FOR CHAPTER 5 & 6 CLASS XIi
1. State the principles: Zone refining, van Arkle process, Liquation
2.Explain the following terms giving a suitable example in each case: emulsification, homogeneous catalysis
2.Explain the following terms giving a suitable example in each case: emulsification, homogeneous catalysis
3 Define
adsorption. Write any two features which distinguish physisorption from
chemisorption.
4. What are associated colloids?
Give two examples. How does associated colloid differ from Multi molecular and macro molecular colloids.
5.Why
NaCN is used in froth floatation process?
6. What
is peptization? Give example.
7. (i) Dialysis is a method of purification of sols. But prolonged dialysis of the
sol makes it
unstable.Why
?
(ii)Out
of CO and NH3 which is adsorbed on activated charcoal to a
large extent and why?
(iii)Out
of PO43–,SO42–, Al3+ and Na+,which will have the highest
coagulating power for As2S3 colloid ?
