Vant Hoff's factor (i) for Na2SO4=3 ∴ΔTf= (i) kfm=3×1.80×10.01=0.0558 K
If sodium sulphate is considered to be completely dissociated into cations and anions in aqueous solution, the change in freezing point of water (ΔTf), when 0.01 mol of sodium sulphate is dissolved in 1 kg of water, is (Kf=1.86 K kg mol−1)
Held on 30 Apr 2010 · Verified 6 Jul 2026.
0.0372 K
0.0558 K
0.0744 K
0.0186 K
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The ratio of mass percentage (w/w) of C : H in a hydrocarbon is $12 : 1$. It has two carbon atoms. The weight (in g) of $CO_2(g)$ formed when $3.38$ g of this hydrocarbon is completely burnt in oxygen is : (Given : Molar mass in g mol$^{-1}$ C : 12, H : 1, O : 16)
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