Question

How many grams of methanol should be added to 10L tank of water to prevent its freezing at 268 K? (Kf is given)

Answer 1

by adding a solute freezing point is further lowered right? then why do we want to prevent it from freezing at -5degree C? and.. when i directly used the formula.. answer is not matching..

Answer 2

@samigupta8 @photon336

Answer 3

yeah if you add solute, the freezing point will be lower, than the normal freezing point of your substance. so it won't freeze at the normal temperature that you'd expect it to.

Answer 4

yes then why have they given to prevent freezing at that temp.? they can only decrease the freezing point right? @Photon336

Answer 5

delta T = Kf *molality when i applied this i didn't get the answer.... @Photon336

Answer 6

@phi @freckles

Answer 7

@samigupta8

Answer 8

What did u do ?
∆T=Kfm...
m is molality u might have applied this formula ryt??

Answer 9

yes i have written abv..that i didnt get the answer..!

Answer 10

268 = x/10 * Kf and found x but ans.. not matching @samigupta8

Answer 11

U r wrong @priyar
The equation is ∆T=Kf m
And not T=Kf m

Answer 12

I know that... @samigupta8 i have already calculated delta T..

Answer 13

U wrote it as 268 =Kf m

Answer 14

Whereas it should be 273-268=Kf m

Answer 15

oops! i didn't covert to kelvin!

Answer 16

*convert

Answer 17

Yep u did take 0°C as the freezing point bt forgot to change it to K