The "3" in CO32- means that

What is the mass of 2.00 l of an intravenous glucose solution with a density of 1.15 g/ml?

Which substance is a steroid? cholesterol fatty acid monosaccharide trans fat

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!