From your notation, it is phosphorus trichloride. Basically, there are three molecules of phosphorus chloride.
Answer:
A. (CH3)3C-I reacts by SN1 mechanism whose rate is independent of nucleophile reactivity.
Explanation:
We must recall that (CH3)3C-I is a tertiary alkyl halide. Tertiary alkyl halides preferentially undergo substitution reaction via SN1 mechanism.
In SN1 mechanism, the rate of reaction depends solely on the concentration of the alkyl halide (unimolecular mechanism) and is independent of the concentration of the nucleophile. As a result of this, both Br^- and Cl^- react at the same rate.
The answer is D, because gems are usually not mettallic
