Order Surface Chemistry and Nuclear Chemistry

Order Surface Chemistry and Nuclear Chemistry
1. The minimum concentration of an electrolyte required to cause coagulation of a sol is called its flocculation value.
It is expressed in millimoles per litre. If the flocculation value of MgSO4
for standard As2
S3
sol is 0.833. How many
milligrams of MgSO4
is to be added to 20 mL standard As2
S3
sol so that flocculation just starts?
2. 0.12 g of dextrin is required to prevent the colour change from red to blue of 200 mL standard Gold sol on adding
2 mL 10% NaCl. Calculate the gold number of dextrin.
3. The formula of a Zeolite used as molecular seive has the formula M56[(AlO2
)56 (SiO2
)136 ]. 250 H2
O. What is the valency
of the metal M?
4. Two alpha particles with energies 7.908 MeV and 7.710 MeV are emitted by an atom of radium. Calculate the wavelength of gamma ray accompanying the decay and express the value in pico meter as a single digit number.
(h = 6.6 u 1034 Js Electronic charge = 1.6 u 1019 coulomb)
5. Carbon from freshly cut piece of wood gives 16000 E emissions per minute per kg and that from an old wooden bowl
gives 500 β emission per minutes per kg. Considering t½ of C – 14 to be 6000 y, calculate the age of the wooden bowl
and express the value as a multiple of 104
years
Order Surface Chemistry and Nuclear Chemistry
6. Calculate the corrected whole number ratio for the time taken for 50% of a radioactive substance to decay to time
taken by it to undergo 9.09% decay
7. Burning of 1 kg coal produce 3.2 × 106
J of heat. Fission of each 241
94 Pu nucleus produce 200 MeV energy. Calculate
the number of 10 g pellets of 241
94 Pu required to produce the same amount of energy by nuclear fission as by burning
1000 tons of coal.
8. Calculate the ratio of the number of E particles produced to number of neutrons captured per atom of 232
9. Assuming no other emission occur in the nucleus, calculate maximum kinetic energy in MeV possessed by β particles
emitted in the process 2