Which of the following statements are TRUE?
(I) Inductive effect operates through the sigma bond
(II) Resonance effect operates through the pi bond
(III) Inductive effects operate through the pi bond
(IV) Resonance effect operates through the sigma bond

The cyclic $\pi$-molecular orbital formed by overlap of p-orbitals must contain,

Identify the reagent used in Etard reaction

An element with a molar mass 27g mol$^{-1}$ forms a cubic unit cell. Calculate the number of atoms present in a unit cell if the density of metal is 2.7g cm$^{-3}$.
$[a^3 \times N_A = 40$ cm$^3$ mol$^{-1}]$