List any four characteristics of a good fuel.
Characteristics of a good fuel are:
i. It should possess low ignition temperature.
ii. It should not leave residue after burning, i.e., it should burn completely.
iii. It should burn without producing too many pollutants.
iv. It should be easily available and accessible
v. Good fuel must be economical.
vi. It should be easy to store and transport.
Write any two differences between binary fission and multiple fission in a tabular form as observed in cells of organisms.
(i) How do you calculate the possible valency of an element from the electronic configuration of its atoms?
(ii) Calculate the valency of element X whose atomic number is 9.
On the basis of electronic configuration, how will you identify the first and the last element of a period?
