1. The nuclide 90Sr is absorbed by bones. This nuclide has a half life of 28.1 years. Suppose one microgram was absorbed by a new-born child, how much 90Sr will remain in his bones after 20 years?
2. Iodine molecule dissociates into atoms after absorbing light of 4500 A0. If one quantum of radiation is absorbed by each molecule, calculate, the kinetic energy of iodine atoms.
(Bond energy of I2 = 240 kJ mol-1
3. Write down the IUPAC name of [Co(NH3)5ONO]Cl2
4. Among the following, the molecule that is linear is
a. CO2 b. SO2
c. NO2 d. ClO2
5. The oxidation number of carbon in CH2O is
a. -2 b. +2
c. +4 d. 0
Sources: JEE paper 1995
JEE screening 1982