Concentrations of lead in the bloodstream are often quoted in units of μg/dl. averaged over an entire region, the mean concentration of lead in the blood was measured to be 1.5 μg/dl. express this concentration in ppb. express your answer to two significant figures.

Calculate the molar mass of aluminum oxide (al2o3). express your answer to four significant figures.

Under normal conditions, describe how increasing the temperatures effects the solubility of a typical salt

I'm learning about the periodic tables and what each subject's configuration is. for example, hydrogen is 1s^1, but i don't understand how you get that. can someone me understand how to figure out how to figure this out? sorry if the question makes no sense, but it would really a lot if you could me understand! you so much if you can!