Choose the aqueous solution below with the lowest freezing point. these are all solutions of nonvolatile solutes and you should assume ideal van't hoff factors where applicable. choose the aqueous solution below with the lowest freezing point. these are all solutions of nonvolatile solutes and you should assume ideal van't hoff factors where applicable.

a. 0.075 m li i
b. 0.075 m (nh4)3po4
c. 0.075 m naio4
d. 0.075 m kcn
e. 0.075 m kno2

B. 0.075 m (NH4)3PO4

Explanation:

Our strategy here is to recall the van´t Hoff factor, i, for the colligative properties of electrolyte solutions which appears as the consequence that electrolytes disociate completely in their solutions in water.

Thus in this problem we need to determine i and then realize the one with the lowest freezing point will have the biggest  i ( all the concentrations are equal) since

ΔTf = i m Kf

Substance  van´t Hoff factor

Li I                             2

(NH4)3PO4              4

NaIO4                       2

KCN                          2

KNO2                       2

The correct answer is B. 0.075 m (NH4)3PO4

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.