Chemistry

(a) Na₂CO₃ -> Solvay

(b) Ti -> Van-Arkel

(c) Cl₂ -> Deacon

(d) NaOH -> Castner – kellner

It is an intramolecular aldol condensation

A > B > C > D

Lone pair is localized in (A) while all 3 have delocalized lone pair but they can be compared by 3° > 2° > 1° because methyl group increases the basicity.

Kindly go through the solution

S > Se > Te > O

Both (A) and (B) are correct but R is not correct explanation of A. In both oxidation state of metal is +1, also both have similar lattice structure.  

(a) Sucrose -> a-D glucose and b-D fructose

(b) Lactose -> b-D- galactose and b-D glucose

(c) maltose -> a-D glucose and a-D-glucose

It does not contains 2^nd most abundant element by weight in earth crust because that is Si Calgon -> Na₂ [Na₄ (PO₃)₆]

$\underset{}{\overset{Watersoluble}{\to }}2N{a}^{+}{\left[N{a}_4{\left(P{O}_3\right)}_6\right]}^{2-}$

$\underset{}{\overset{C{a}^{2+}}{\to }}2N{a}^{+}{\left[N{a}_{2}Ca{\left(P{O}_3\right)}_6\right]}^{2-}$

Ceric ammonium nitrate is used to test alcohol while CHCl₃/alc. KOH is used to test 1° amine