Missy Mae is given an unknown white ionic solid which contains of one cations, N
ID: 538660 • Letter: M
Question
Missy Mae is given an unknown white ionic solid which contains of one cations, Na^+, K^+, Ca^2+ and one of the anions Cl, ^- NO_3^-, SO_4^2- Write the formulas of all the possible ionic compounds which could be the unknown compound. Missy Mae performs a flame test on the unknown compound, which reveals a lilac color. An aqueous solution of the unknown compound yields the following results. forms no precipitate when 0.10 M sodium sulfate is added Forms a precipitate when 0.10 M silver nitrate is added Forms no precipitate when 0.10 M barium nitrate is added What is the formula of the unknown compound? Explain your reasoning. There is no precipitation test for nitrate ion. Explain why this is the case.Explanation / Answer
1]
NaCl
KNO3
CaSO4
2]
Lilac colour is given by ----> K cation in flame test
White precipitate by Cl - ion on reaction with AgNO3
Formula ==> KCl
3]
Nitrate ion has the possibility of creating hydrogen bonds with water thus making its distribution in thewater matrix stable.
So nitrate ion does not form precipitate with any metals.