Question

Anhydrous ferric chloride is prepared by:
A. Heating hydrated ferric chloride at a high temperature in a stream of air.
B. Heating metallic iron in a stream of dry chlorine gas.
C. Reaction of ferric oxide with $HCl(aq)$
D. Reaction of metallic iron with $HCl(aq)$

Answer 1

Ferric chloride $FeC{l_3}$ is an orange to brown-black coloured solid. It is very less soluble in water ${H_2}O$. also ferric chloride is non-combustible.

Complete step by step solution:
Anhydrous ferric chloride has structural symmetry as that of the $Bi{I_3}$ structure, with an octahedral $F{e_3}$ molecules center are interconnected by two-coordinate chloride. A ferric chloride has a low melting point and its boiling point is around $315^\circ C$. The vapour state consists of the light aluminium chloride which extremely dissociates in the ferric chloride $FeC{l_3}$ (with ${D_{3h}}$ point which has a group molecule symmetry) at a higher temperature, in competition with its reversible decomposition to give ferrous chloride and chlorine gas
It is used for treating sewage, industry waste material, to purify water and as an etching agent for designing printed circuit boards, also to manufacture other types of chemicals. Ferric chloride solution is visible as a colorless to light brown aqueous and anhydrous solution that has a light hydrochloric $HCl$ acidic smell.
An anhydrous ferric chloride lasts for about approx. Six months.
Anhydrous ferric chloride is prepared by passing dry Chlorine gas $C{l_2}$ gas over heated iron $Fe$ metal fillings.
The complete process of chemical reaction is given as below,
$2Fe + 3C{l_2}\xrightarrow{\Delta }2FeC{l_3}$
So, dry chlorine gas is reacted with iron only if iron is in a heated form.

**Therefore, the correct answer is option B. Heating metallic iron in a stream of dry chlorine gas.

Note: **
A ferric chloride is a kind of harmful, extremely corrosive and acidic in nature. The anhydrous material is a strong dehydrating agent. Although reports of poisoning in humans are seen in rare cases, consumption of ferric chloride can result in serious fatality and mortality.