For a reaction consider the plot of $$\ell $$n k versus 1/T given in the figure. If the rate constant of this reaction at 400 K is 10^–5 s^–1, then the rate constant at 500 K is –

The aldehydes which will not form Grignard product with one equivalent Grignard reagents are -

If the de Broglie wavelength of the electron in n^th Bohr orbit in a hydrogenic atom is equal to 1.5 $$\pi $$a₀ (a₀ is Bohr radius), then the value of n/z is -

The element that does NOT show catenation is :