Compare the charges and masses of protons neutrons and electrons

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.

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.

How many moles is 14.5 cm^3 of platinum? the density of platinum is 21.45 g/cm^3.