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# Which of the following statements are NOT correct?

(1) In an aqueous solution chlorine is a stronger oxidizing agent than flourine

(2) Red phosphorous is less volatile than white because the former has a tetrahedral structure.

(3) The decreasing order of electron affinity of F, Cl, Br is F > Cl > Br

(4) Graphite is a better lubricant on the moon than on the earth.

$\begin{array}{1 1} (A) (1), (3) and (4) \\ (B) (2), (3) and (4) \\ (C) (1), (2) and (3) \\ (D) \text{All of the statements are incorrect}\end{array}$

Ans: (D) All of the statements are incorrect
(1) In an aqueous solution chlorine is a stronger oxidizing agent than fluorine $\rightarrow$ The oxidizing ability falls as you go down the Group 7, so Fl > Cl > Br > I.
(2) Red phosphorous is less volatile than white because the former has a tetrahedral structure $\rightarrow$ Red phosphorus has polymeric structure in which many tetrahedra are joined to each other by covalent bonds. Therefore it has a polymeric structure due to which it is less volatile than white phosphorous.
(3) The decreasing order of electron affinity of F, Cl, Br is F > Cl > Br $\rightarrow$ The largest repulsion in F due to smaller size make its electron affinity less than that of Cl. Therefore, the correct order is F < Cl > Br.
(4) Graphite is a better lubricant on the moon than on the earth $\rightarrow$ Graphite is best suited for lubrication in air. Water vapor is a necessary component for graphite lubrication. The adsorption of water reduces the bonding energy between the hexagonal planes of the graphite to a lower level than the adhesion energy between a substrate and the graphite. Because water vapor is a requirement for lubrication, graphite is not effective in vacuum.