Question

How many moles of $B{H}_3$ are needed to react completely with 2 moles 1 pentene in hydroboration-oxidation reaction?

• A. 2 moles
• B. 3 moles
• C. 2/3 moles
• D. 3/2 moles

Answer 1

Answer: (C)

2/3 moles

As $3$ moles of $B{H}_3$ reacts completely with $1$ mole of the alkene.

Now for 2 moles of an alkene, we require $\frac{2}{3}$ moles of $B{H}_3$.