Jawab

a. Mr MgSO₄ = 120 g/mol

b. Mr K₂Cr₂O₇ = 294 g/mol

c.  Mr Fe₂(SO₄)₃= 400 g/mol

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Penjelasan

Diketahui nilai beberapa Relative Atomic Mass beberapa atom :

Ar Mg = 24 g/mol

Ar S = 32 g/mol

Ar O = 16 g/mol

Ar K = 39 g/mol

Ar Cr = 52 g/mol

Ar Fe =  56 g/mol

Perhitungan Relative Molecular Mass (Mr) senyawa :

a. Mr MgSO₄ = Ar Mg + Ar S + 4 Ar O

Mr MgSO₄ = 24 + 32 + 4 x 16 = 120 g/mol

b. Mr K₂Cr₂O₇ = 2 x Ar K + 2 x Ar Cr + 7 x Ar O

Mr K₂Cr₂O₇ = 2 x 39 + 2 x 52 + 7 x 16 = 294 g/mol

c. Mr Fe₂(SO₄)₃ = 2 x Ar Fe + 3 x Ar S + 3 x 4 x Ar O

Mr Fe₂(SO₄)₃ = 2 x 56 + 3 x 32 + 12 x 16 = 400 g/mol

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Pelajari Lebih Lanjut

Perhitungan Mr : yomemimo.com/tugas/6143299