Jawabanmu

2014-04-27T11:57:34+07:00
PH = - Log (OH-)
9   = - log OH-
OH- = 10^-9
OH - = b/g x Kb
10^-9 = 0,05/g x 10^-5
0,05 mol g = 10^-9/10^-5
g = 10^-4/0,05
g (mol garam/ (NH4)2SO4) = 0,002 mol >>>>>>> Mr (NH4)2SO4 = 36 + 96 = 132
mol = gr/Mr
0,02 = gr/132
gr = 132 x 0.02 = 2,64 gram

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