delta T = ikfm
delta T is the amount f.p. is lowered.
i is the number of particles; i.e., Na3PO4 will have i = 4 (3 for Na and 1 for PO4).
m is molality.
k is a constant and need not enter into the calculations.
Arrange the following solutions in order of decreasing freezing point.
0.20 m Na3PO4
0.35 m NaCl
0.30 m MgCl2
0.15 m C6H12O6
0.05 m CH3COOH
So, start with the first part. If i=4 and m=0.2, then delta T = 0.8. Do that for all of them and write from biggest to smallest.
actually,
delta T = iKm = 4*K*0.2 = 0.8K (you omitted the K. Although you will not need to use K, delta T is 0.8*K and not 0.8 degrees.)
You want the items to be arranged in DECREASING f.p. and since delta T is original f.p. - new f.p., then delta T will the lowest f.p. when it is the largest. So it seems to me you want to go from the smallest delta T to the largest delta T. Check my thinking.
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