Question

Solubility Rules

Compounds containing group 1 alkali metals or ammonium (NH4+) are soluble.
Nitrates (NO3−), chlorates (ClO3−), perchlorates (ClO4−), and acetates (C2H3O2−) are soluble.
Chlorides (Cl−), bromides (Br−), and iodides (I−) are soluble, except for compounds containing silver (Ag+), mercury(I) (Hg22+), and lead (Pb2+).
Sulfates (SO42−) are soluble, except for compounds containing calcium (Ca2+), strontium (Sr2+), barium (Ba2+), and lead (Pb2+).
Hydroxides (OH−), carbonates (CO32−), and phosphates (PO43−) are insoluble, except for compounds containing group 1 alkali metals and ammonium (NH4+).
Sulfides (S2−) are insoluble, except for compounds containing group 1 alkali metals, ammonium (NH4+), magnesium (Mg2+), calcium (Ca2+), strontium (Sr2+), and barium (Ba2+).

Answer 1

The answer is E, BaSO4

GOOOOOD LUCK DADDY

Answer 2

All column 1 and Ammonium ion are soluble. That lets out A

Rule 1 says the nitrates are all soluble. That eliminates B

All column 1 compounds are soluble. That does C in. (C is Not the answer).

D is very nasty. You don't have any way to eliminate it. But two metals as reactive as K and Ba won't combine by ionization. In fact they shouldn't combine at all. D is incorrect.

E is the answer. All Sulfates react with any metal except a couple. Ba+2 is one of the exceptions.

Answer: E