An unknown element X has the following isotopes: ⁵²X (79.50% abundant), ⁴⁹X (8.00% abundant), ⁵⁰X (12.50% abundant). What is the average atomic mass in amu of X?

What is the mass defect of a mole of nuclei with 1.8 x 10^15 j/mol binding energy?

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.

What is the solubility-product constant of barium sulfate, baso4, if a saturated solution is 1.03 ´ 10-5 m?