Question #5b2a9
1 Answer
B. Magnesium
Explanation:
The trick here is the to find the ion which reacts to form a insoluble compounds.
SOLUBILITY RULES
-
All common compounds of
"NH"_4^+ and the Group 1 elements are soluble. -
"NO"_3^"-", "ClO"_3^"-", "ClO"_4^"-", "C"_2"H"_3"O"_2^"-" — all common nitrates, chlorates, perchlorates, and acetates are soluble. -
"F"^"-", "Cl"^"-", "Br"^"-", "I"^"-" — all halides are soluble except those of"Ag"^+, "Hg"_2^"2+", "Pb"^"2+" and the fluorides of"Mg"^"2+", "Ca"^"2+", "Sr"^"2+" , and"Ba"^"2+" . -
"SO"_4^"2-" — most sulfates are soluble EXCEPT those of"Sr"^"2+", "Ba"^"2+", "Ca"^"2+", "Pb"^"2+" ,"Hg"_2^"2+" , and"Hg"^"2+" . -
"CO"_3^"2-", "C"_2"O"_4^"2-", "OH"^"-", "O"^"2-", "SO"_3^"2-", "PO"_4^"3-", "CrO"_4^"2-", "S"^"2-" — all carbonates, oxalates, hydroxides, oxides, phosphates, chromates, and sulfides are insoluble. Remember the first rule. all the Group 1 elements are soluble independent of their ion attached to them.
So if you do a reaction with
So NaCl is soluble as we know
Doing a reaction with potassium ion.
Recall the first rule
All common compounds of the Group 1 elements are soluble.
Doing a reaction with
Recall the 4th rule.
Thus
Doing a reaction with magnesium
And that's your solution because
Most carbonates are insoluble except the elements in group 1.
Magnesium is not in group 1` and thus it is insoluble