HELP ME PLSSS FAST PLS

Which best describes why nh4+ can form an ionic bond with cl-?

How many molecules of sucrose c12h22o11 are there in 454 grams of sucrose

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!