In the nitration of bromobenzene, a mixture of nitric acid and sulfuric acid are added to the bromobenzene and stirred at room temperature. Why is it important to keep the reaction mixture at room temperature rather than heating it?

a. To prevent bromobenzene from evaporating out of solution.

b. To prevent bromobenzene from precipitating out of solution.

c. To prevent di-substituted products from forming.

d. To prevent meta-substituted products from forming.

e. To prevent meta-substituted and di-substituted products from forming.

Lab reagent, hypothesis test. a reference solution used as a lab reagent is purported to have a concentration of 5 mg/dl. six samples are taken from this solution and the following concentrations are recorded: (5.32, 4.88, 5.10, 4.73, 5.15, 4.75) mg/dl. these six measurements are assumed to be an srs of all possible measurements from solution. they are also assumed to have a standard deviation of 0.2, a normal distributin, and a mean concentration equal to the true concentration of the solution. carry out a significance test to determine whether these six measurements provide reliable evidence that the true concentration of the solution is actually not 5 mg/dl.