In 1912, chemist fritz haber developed a process that combined nitrogen from the air with hydrogen at high temperatures and pressures to make ammonia. specifically, the process involved combining one molecule of nitrogen gas (n2) with three molecules of hydrogen gas (h2) to get two molecules of ammonia (nh3). if you write this process in a symbol format, it looks like this: n2 3h2 → 2nh3explain whether this is a chemical or physical change, and why. does it involve elements, compounds, mixtures, or pure substances? also describe how many atoms are involved before and after. what do you notice about the number of atoms?

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.