Kaplan freezing point question

[joonkimdds]

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When 22.2g of a soluble ionic compound(formula weight = 111g/mol) are added to 1.0kg of water(Kf=1.86celcius/m), the freezing point of the resulting solution is -1.12celcius. Which of the following could be the general formula of the ionic compound?

answer= MX2


the solution says
delta Tf = Kf M
[22.2g x (1mol/111g)] / 1K of water = 0.2

and then they multiplied this by 2 to get 0.4 celcius because 2 is the number of particles formed, but I don't know how we can tell how many particles are formed.

and then also, they said -1.12 is 3 times as much as the calculated value
but the calculated value is 0.4 celcius so I don't know how it's 3 times more than -1.12.

 

[PD3]

Set up: 1.12= i [(22.2/1110*1.86]

Solve for i and you get 3, thus there must be three particles from the compoung. An example would be CaCl2

 

[joonkimdds]

Set up: 1.12= i [(22.2/1110*1.86]

Solve for i and you get 3, thus there must be three particles from the compoung. An example would be CaCl2

ty ty ty ty ty ty ty ty ty ty ty ty ty ty ty ty ty ty ty so much 😍

 

[PD3]

No problem.