Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

NEET Class neet Answered

By dissolving 5g substance in 50g of water, the decrease in freezing point is 1.2 degree celcius. The gram molal depression is 1.85 degree celcius. The molecular weight of substance is (a)105.4 (b)118.2 (c)137.2 (d)154.2  
Asked by Balbir | 28 Jul, 2019, 06:08: PM
answered-by-expert Expert Answer
Option (d) is correct.
 
Given:
 
ΔTf = 1.2 ºC
 
Wsolvent = 50 gm
 
Wsolute = 5 gm
 
Kf = 1.85 ºC gm/mol
 
Using the formula od depression in freezing point, molecular weight of the subastance can be calculated as,
 
straight M subscript 2 space equals space fraction numerator straight K subscript straight f cross times straight W subscript solute cross times 1000 over denominator increment straight T subscript straight f space cross times space straight W subscript solvent end fraction space space space space space space equals fraction numerator 1.85 cross times 5 cross times 1000 over denominator 1.2 cross times 50 end fraction straight M subscript 2 space equals space 154.166 straight M subscript 2 space almost equal to space 154.2 space straight g divided by mol
 
Molecular weight of the subastance is 154.2 g/mol
Answered by Varsha | 29 Jul, 2019, 09:51: AM

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
NEET neet - Chemistry
solutions
question image
Asked by 8239682116rahul | 10 Apr, 2024, 01:48: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
NEET neet - Chemistry
The specific conductance of N/10 kcl solution at 20°C is 0.0212ohm–1 cm–1 and the resistance of the cell containing this solution at 20°C is 55ohm the cell constant
Asked by ramadevisupriya5678 | 28 Mar, 2024, 02:18: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
NEET neet - Chemistry
physics
question image
Asked by kavyamodi237 | 11 Jul, 2022, 06:26: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
NEET neet - Chemistry
Why vacuum pump is inserted in the final collecting beaker and not in the first flask (in which the two liquids are present initially) in distillation under reduced pressure process?
Asked by myindiaisbad | 17 Jun, 2022, 11:17: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
NEET neet - Chemistry
chemistry
question image
Asked by bhaveshkaria31 | 30 May, 2022, 09:26: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
NEET neet - Chemistry
the boiling point of 0.15 molar aqueous solution of an unknown solute is 373.23 K at 1 atm . The molal elevatio constant of water is ______ K kg mol ^(-1)
Asked by rautganesh2255 | 01 Jul, 2021, 09:32: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
NEET neet - Chemistry
show that total vapour pressure over the solution of two liquids 1&2 at a particular temperature varies linearly with the mole fraction of a components
Asked by NituBarman192 | 01 Jun, 2021, 10:22: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
NEET neet - Chemistry
What is the solution sir ?
question image
Asked by bhagirathdangi12345 | 12 Feb, 2021, 01:42: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
NEET neet - Chemistry
Please explain this
question image
Asked by akashmanu09 | 08 Jan, 2021, 10:21: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
NEET neet - Chemistry
What are protic and aproticsolutions 
Asked by arnavvidudala20050 | 17 May, 2020, 03:07: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt
Get Latest Study Material for Academic year 24-25 Click here
×