Agas of unknown molecular mass was allowed to effuse through a small opening under constant-pressure conditions. it required 105 s for 1.0 l of the gas to effuse. under identical experimental conditions it required 31 s for 1.0 l of o2 gas to effuse. calculate the molar mass of the unknown gas. (remember that the faster the rate of effusion, the shorter the time required for effusion of 1.0 l; in other words, rate is the amount that diffuses over the time it takes to diffuse.)

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.