S8, I2, SiO2, SO2, C6H6
The answer is SiO2 but I need to know why.. I think the first to have London dispersion but aren't the following three all nonpolar and London d too... So does that mean the heaviest one out of those three will be the one with highest MP? tell me if my reasoning is ok or tell me yours... Please only answer if you know!
The answer is SiO2 but I need to know why.. I think the first to have London dispersion but aren't the following three all nonpolar and London d too... So does that mean the heaviest one out of those three will be the one with highest MP? tell me if my reasoning is ok or tell me yours... Please only answer if you know!
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This all has to do with the Van't Hoff Factor (i). i represents the number of ions each molecule will split into. The important concept of i is that the higher i is, the higher the boiling point or the lower the freezing point. For example, a compound with i=3 will have a higher boiling point/lower freezing point than a compound with i=2.
Now that we have determined what i is, we must know how to find it. Knowing that i is the number of ions a compound will break into, we have to go through each given compound and determine i.
S8: i=1 (anything by itself isn't going to break up)
I2: i=1 (anything by itself isn't going to break up)
SiO2: i=3 (Si breaks into one, O breaks into one, O breaks into one)
SO2: i=1 (covalent compound. it won't break up)
C6H6: i=1 (covalent compound. it won't break up)
Remember: polyatomic ions and covalent compounds will not break up. For example, magnesium nitrate, Mg(NO3)2, will have an i=3 because the Mg will break into one, the NO3[-1 charge] will break into one, and the other NO3[-1 charge] will break into one.
Anyway, since SiO2 has the highest Van't Hoff Factor, it is going to have the highest boiling/lowest freezing point. Therefore, SiO2 is your answer.
Now that we have determined what i is, we must know how to find it. Knowing that i is the number of ions a compound will break into, we have to go through each given compound and determine i.
S8: i=1 (anything by itself isn't going to break up)
I2: i=1 (anything by itself isn't going to break up)
SiO2: i=3 (Si breaks into one, O breaks into one, O breaks into one)
SO2: i=1 (covalent compound. it won't break up)
C6H6: i=1 (covalent compound. it won't break up)
Remember: polyatomic ions and covalent compounds will not break up. For example, magnesium nitrate, Mg(NO3)2, will have an i=3 because the Mg will break into one, the NO3[-1 charge] will break into one, and the other NO3[-1 charge] will break into one.
Anyway, since SiO2 has the highest Van't Hoff Factor, it is going to have the highest boiling/lowest freezing point. Therefore, SiO2 is your answer.