NTA Abhyas JEE Main2020ChemistrySolutionsPractice
A solution containing 1.8 g of a compound (empirical formula CH 2 O ) in 40 g of water is observed to freeze at - 0 .465 ∘ C . The molecular formula of the compound is- ( K f of water = 1 .86 kg K mol - 1 )
Options
- AC 2 H 4 O 2
- BC 3 H 6 O 3
- CC 5 H 10 O 5
- DC 6 H 12 O 6
Correct answer
D. C 6 H 12 O 6
Step-by-step solution
M 2 = K f × w 2 × 1000 △ T f × w 1 or M 2 = 1 .86 × 1 .8 × 1000 0 .465 × 40 = 180 n = 180 emp . formula mass = 180 30 = 6 Molecular formula of the compound is C 6 H 12 O 6 .