Statement -1 : Actinoids are very difficult to study.
Statement-2 : Actinoids are radioactive elements having very short half lives especially of later members of actinides.

Statement-1: The study of chemistry of radon is very difficult Statement-2: Radon is radioactive with very short half-life

Statement-1 : Nitrates are not wide spread in the earth's crust. Statement-2 : Nitrate are all very soluble in water.

Statement-1: Promethium is a man mae element. Statement-2: It is radioactive and has been prepared by artifical means.

Statement-1 : Liquid NH_(3) is used for refrigeration. Statement-2 : Enthalpy of vapourisation of ammonia is very large.

Statement -1: Cyclotron does not accelerate electron. Statement-2: Mass of the electron is very small.

Statement-1 : Liquid NH_(3) is used for refrigeration. Statement-2 : Enthalpy of vapourisation of ammonia is very large.

Statement-1: Decarboxylation of beta - keto acid is very difficult and Statement-2: Decarboxylation takes place via a six membered cyclic transition state.

Statement-1: Decarboxylation of beta - keto acid is very difficult and Statement-2: Decarboxylation takes place via a six membered cyclic transition state.

Staements I: To determine the age of certain very old oragnic samples, dating of the sample with radioactive isotpes having larger half-life is a better choice than with radioactive isotopes having smaller half-lives. Staements II: The activity of a radioactive sample having smaller half-life is negligibly small after a very long time and hence makes it next to impossible to get dtected.

Staements I: To determine the age of certain very old oragnic samples, dating of the sample with radioactive isotpes having larger half-life is a better choice than with radioactive isotopes having smaller half-lives. Staements II: The activity of a radioactive sample having smaller half-life is negligibly small after a very long time and hence makes it next to impossible to get dtected.