tentukan Mr dari : a. NH4NO3 b. K2Cr2O7 c. CaCl2 d. Cr(ClO4)3 e. Ba(OH)2

a. NH4NO3
Mr = (ar N x 1) + (ar H x 4) + (ar N x 1) + (ar O x 3)
= (14 x 1) + (1 x 4) + (14 x 1) + (16 x 3)
= 14 + 4 + 14 + 48
= 80g/mol.

b. K2Cr2O7
Mr = (ar K x 2) + ( ar Cr x 2) + (ar O x 7)
= (39 x 2) + (52 x 2) + (16x 7)
= 78 + 104 + 112
= 294gr/mol.

c. CaCl2
Mr = (ar Ca x 1) + (ar Cl x 2)
= (40 x 1) + (35,5 x 2)
= 40 + 71
= 111gr/mol

d. Cr(ClO4)3
Mr = (ar Cr x 1) + (ar Cl x 3) + (ar O x 12)
= (52 x 1) + (35,5 x 3) + (16 x 12)
= 52 + 106,5 + 192
= 350,5 gr/mol.

e. Ba(OH)2
Mr = (ar Ba x 1) + (ar O x 2) + (ar H x 2)
= (137 x 1) + (16 x 2) + (1 x 2)
= 137 + 32 + 2
= 171gr/ mol