Jawabanmu

2014-09-02T20:36:34+07:00
Kf = 1,86
gr = 40% = 0,4 gr
Mr = 40
jadi m = gr/Mr ⇔ 0,4/40 = 0,01

⇒ ΔTf = Kf . m 
⇒ ΔTf = 1,86 . 0,01
⇒ ΔTf = 0,0186
ΔTf = Tfo - Tfl
0,0186 = 0 - Tfl
Tfl = 0 - 0,0186
Tfl = -0,0186 derajat C

maaf kalau saya salah :v

1 5 1
2014-09-02T20:43:15+07:00
Larutan NaOH 4%= 4 gram,jadi larutan H2O = 96 gram
ΔTf = m.Kf
ΔTf = g:Mr x 1000:P x Kf
ΔTf = 4 :40 x 1000: 96 x1,86
=1,934 C
≤Titik beku larutan =0-1,934 =- 1,934
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