Final answer:
The question lists potential products from a reaction involving tert-butanol but does not provide sufficient data to identify the specific product or calculate the mole ratio; none of the listed compounds is tert-butanol, which actually has the formula (CH3)3COH.
Step-by-step explanation:
The question pertains to a reaction involving tert-butanol and a chloride/bromide mixture that yields a product with a refractive index of 1.407. The question lists several compounds but does not provide enough information to determine the exact product or mole ratio. However, none of the compounds listed (a-d) correctly represents tert-butanol, which actually has the formula (CH3)3COH (2-methyl-2-propanol). The question likely refers to the reaction of tert-butanol with a halogen to produce either tert-butyl chloride or tert-butyl bromide. To determine the structure of the compound with the given refractive index and calculate the mole ratio, additional data such as chemical analysis or reaction conditions would be required.