One among the lanthanoids, Ce(III) (Z=58) can easily be oxidised to Ce (IV). Explain why?

Boron trifluoride can easily reacts with NH_(3) . Explain why?

The stable oxidation state of Ce (Z = 58) is

The cap of the pen can be easily opened with the help of tw fingers than with one finger. Explain why.

Which of the following haloalkanes reacts with aqueous KOH most easily ? Explain giving reason. (i) 1-Bromobutane (ii) 2-Bromobutane (iii) 2-Bromo-2-methyipropane (iv) 2-Chlorobutane

Give the correct order of initials T(true)F(false) for following satements. (I) If electron has zero quantum magnetic numbers, then it must be present in s-orbital (II) In orbital diagram, Pauli's exclusion principal is violated (III) Bohr's model can explain spectrum of the hydrogen atom. (IV) A d-orbital can accommodate maximum 10 electrons only.

Among the ionic species Sc^(3+) , Ce^(4+) and Eu^(2+) which one is a good oxidizing agent ? Give a suitable reason for your answer. (At no. Sc = 21, Ce = 58, Eu = 63)