Barium (Ba) is located in Group 2A, Period 6 because we know that Barium (Ba) has two valence electrons (All elements in Group 2A have two valence electrons ) and is located in the 6s subshell (the sixth period) therefore it's in Group 2A, Period 6
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Group 2A, Period 6
Group 2A Period 6
periods are the rows on the table. which also refer to the elctrons in the outermost subshell. so, its i the 6th shell. which means its in the 6th line down. and it's 2 over, so it's in group 2