Problem: A student was given a solid containing a mixture of nitrate salts. The sample completely dissolved in water, and upon addition of dilute HCl, no precipitate formed. The pH was lowered to about 1 and H2S was bubbled through the solution. No precipitate formed. The pH was adjusted to 8 and H2S was again bubbled in. This time, a precipitate formed. Which compounds might have been present in the unknown?a) Ca(NO3)2b) AgNO3c) Fe(NO)3d) Cr(NO3)3e) Cu(NO3)2f) Bi(NO3)2g) Co(NO3)2h) KNO3

FREE Expert Solution

Solubility Rules:

Soluble Ionic Compounds:

 Group 1A ions (Li+, Na+, K+, etc.) and Ammonium ion (NH4+) are soluble
Nitrates (NO3-), Acetates (CH3COO- or C2H3O2-), and most Perchlorates (ClO4-) are soluble
Cl-, Br-, and I- are soluble except when paired with Ag+, Pb2+, Cu+, Hg22+
Sulfates (SO42-) are soluble except those of Ca2+, Sr2+, Ba2+, Ag+, and Pb2+

• Insoluble Ionic Compounds:

89% (52 ratings)
View Complete Written Solution
Problem Details

A student was given a solid containing a mixture of nitrate salts. The sample completely dissolved in water, and upon addition of dilute HCl, no precipitate formed. The pH was lowered to about 1 and H2S was bubbled through the solution. No precipitate formed. The pH was adjusted to 8 and H2S was again bubbled in. This time, a precipitate formed. 

Which compounds might have been present in the unknown?

a) Ca(NO3)2

b) AgNO3

c) Fe(NO)3

d) Cr(NO3)3

e) Cu(NO3)2

f) Bi(NO3)2

g) Co(NO3)2

h) KNO3

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Molecular Equations concept. You can view video lessons to learn Molecular Equations. Or if you need more Molecular Equations practice, you can also practice Molecular Equations practice problems.