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Fill in the coefficients that will balance the following reaction: a0cr2(so4)3 + a1agno3

Elements in group 2 are all called alkaline earth metals. what is most similar about the alkaline earth metals?

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!