Question

calcule a massa molecular Ba(OH)2

Answer 1

Ba = 137,7g/mol
OH = 17,01g/mol

Ba(OH)2  137,7 + 17,01X2 =137,7 + 34,02 = 171,72g/mol

Answer 2

Ba = 137 u
O = 16 u
H = 1 u

MM= 137 + 16 . 2 + 1 . 2
MM= 137 + 32 + 2
MM = 171 u