Question

What will the reaction of diborane with chlorine produce?
A) ${B_2}{H_5}Cl$
B) ${H_2}$
C) $BC{l_3}$
D) (B) and (C) both

Answer 1

Hint: As we know that Diborane is a chemical compound made up of boron and hydrogen atoms. It is highly reactive and reacts with halogen very vigorously hence it is reacted under controlled conditions to give a good yield.

Complete answer
As we know that diborane $({B_2}{H_6})$ is a composed of boron and hydrogen atoms and it is used for industrial production of boron trioxide by direct chlorination. One mole of diborane reacts with six moles of chlorines to produce two moles of boron trichloride $(BC{l_3})$ along with six moles of hydrogen chloride. We can represent this through an equation as:
${B_2}{H_6} + 6C{l_2} \to 2BC{l_3} + 6HCl$

Diborane is highly reactive and very versatile so it is used in the reaction under controlled conditions to yield a good amount of product that is boron trichloride.

Diborane reacts with water to form boric acid and hydrogen gas. It also reacts with hydrogen chloride or hydrogen bromide and results in the formation of boron halohydrin (${B_2}{H_5}Cl$). Hence these are incorrect products.

Additional information:
Diborane is generally used for carboxylic acids reduction in the presence of esters, halides and amides. It is also flammable and available in gaseous form. When boron trichloride reacts with lithium aluminium hydride or boron trifluoride it results in the production of diborane. It has irritant properties also and causes tightness of chest and shortness of breath kind of symptoms while exposure. It is also used in rocket propellants but it does not show complete combustion reaction and results in boron monoxide formation.

Therefore, the correct answer is option (C).

Note: Diborane is used in synthesis of organic reagents for hydroboration and commonly used as reducing agents. It is a vigorously acting compound and gives boron trichloride on direct chlorination which is industrially used. It also readily reacts with water to produce boron trioxide and gives off water molecules.