Mass 7 g/ml divided by 10 ml volume what is the density

What is the molar mass of a gas that has density of 2.054 g/l

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.

Which of the following statements is true about energy quantization at the atomic level? electrons in the outermost orbits are the most stable. electrons in all the orbits around the nucleus have the same amount of energy. electrons in the orbit closest to the nucleus have the least amount of energy. electrons absorb or release the same amount of energy independent of the energy levels.