Given, molality, mΔTfkfΔTfi=0.0020 m=0∘C−0.00732∘C=0.00732∘C=1.86∘C/m=i⋅kf×m=kf×mΔTf=1.86×0.00200.00732=1.96≈2 Since, the compound is ionic, so number of moles produced is equal to vant' Hoff factor, i. Hence, 2 moles of ions are produced. 
A 0.0020 ~m aqueous solution of an ionic compound Co ( NH_3 )_5 ( NO_2 ) Cl freezes at -0.00732° C. Number of moles of ions which 1 ~mol of ionic…
NEET UG 2009 — Chemistry Physical Chemistry
2009mcqhard
A 0.0020 m aqueous solution of an ionic compound Co(NH3)5(NO2)Cl freezes at −0.00732∘C. Number of moles of ions which 1 mol of ionic compound produces on being dissolved in water will be (kf=−1.86∘C/m)
Official previous-year question
Held on 30 Apr 2009 · Verified 9 Jul 2026.
Options
- A
2
- B
3
- C
4
- D
1
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