Solubility rules homework Help at TutorEye

Are you a university or school looking for an online tutoring partnership ? Talk to Us

Solubility rules:


Solubility rules are sets of rules predicting the solubility combinations of different cations and anions and on mixing with each other.
(aq) represents soluble combinations
(s) represents insoluble combinations
(d) represents decomposition (complex reactions) 


Density of water Sample Questions:



Question 1: Based on the solubility rules, which one of the following compounds should be insoluble in water?


a) Na2So4
b) CuSO4
c) BaSO4
d) MgSO4


Answer: Option c)  BaSO4


Explanation: Among the given options, BaSO4 insoluble in water. Most sulfate salts are soluble. Na2So4 ,CuSO4 , MgSO4 are all soluble in water.


Get the full solution!


Question 2: Which one of the following salts are mostly insoluble in water?


a) Nitrates
b) Sulfates
c) Carbonates
d) Halides


Answer: Option c) Carbonates


Explanation: Carbonates are frequently insoluble in water. Nitrates, sulfates, halides all are mostly soluble in water.


Get the full solution!


Question 3: Which of the following salt is slightly soluble in water?


a) Chromates
b) Hydroxide
c) Sulfate
d) Nitrate


Answer: Option b) Hydroxide


Explanation: Most hydroxides are insoluble in water, But some like calcium hydroxide and barium hydroxide are slightly soluble.


Get the full solution!


Question 4: Which of the following are always soluble in water?


a) Alkali metals 
b) Fluorides
c) Sulfates
d) Chromates


Answer: Option a) Alkali metals


Explanation: Salts containing Group 1 elements also known as alkali metals (Li+, Na+, K+, Cs+, Rb+) are soluble in water. Rest of the mentioned salts have exceptions.


Get the full solution!


Question 5: Which of these substances is likely to form a precipitate?


a) Nacl 
b) AgBr


Answer: Option b) AgBr


Explanation: Bromides are usually soluble but salts of silver are mostly insoluble. AgBr is insoluble and forms precipitate.


Get the full solution!


Question 6: There will be precipitates formed in the following reaction


2NaOH + K2CrO4 → KOH+Na2CrO4


a) True
b) False


Answer: Option b) False


Explanation: KOH is hydroxide of alkali metal potassium. Salts of alkali metals are soluble and hence KOH is soluble. also is a salt of alkali metal Na and hence it is soluble too. Both the products are soluble. Therefore, no precipitate will be formed in this reaction


Get the full solution!


Question 7: Which of the following salts is insoluble in water?


a) Sodium phosphate
b) Barium hydroxide
c) Magnesium carbonate
d) Potassium nitrate


Answer: Option c) Magnesium carbonate


Explanation: Carbonate salts are usually insoluble in water with few exceptions like when carbonate is paired with an alkali metal. Magnesium carbonate is considered an insoluble salt. 


Get the full solution!


Question 8: Which of the following statements is incorrect according to solubility rules?


a) Ammonium salts are considered soluble
b) Salts containing a nitrate ion are considered soluble
c) Phosphate salts are generally considered soluble
d) Ionic compounds with halogens are generally soluble


Answer: Option c) Phosphate salts are generally considered soluble


Explanation: According to solubility rules the salts containing alkali metals, nitrate ions, ammonium ions are considered soluble. Phosphates, on the other hand, are generally considered insoluble, unless it is paired with an alkali metal or ammonium ion.


Get the full solution!


Question 9: Substances for which pure water would not be an efficient solvent are?


a) Those that have high charge densities
b) Those that have large dipole moments
c) Those with evenly dispersed electrons
d) Those that tend to form hydrogen bonds


Answer: Option c) Those with evenly dispersed electrons


Explanation: Water is a polar molecule, it dissolves substances having electrostatic charge due to electronic arrangement. Evenly dispersed electrons means a nonpolar molecule which will not dissolve in water.


Get the full solution!


Question 10: Which of the following molecules is insoluble?


a) Mg(NO3)2
b) AgCl
c) KBr
d) AgNO3


Answer: AgCl


Explanation: According to solubility rules, alkali metal salts and ammonium salts are soluble, all nitrates, acetates, and perchlorates are soluble and mercury, lead, and silver salts are insoluble.
Therefore, AgCl is insoluble.



Get the full solution!



Frequently Asked Questions



What are solubility rules?

Following are the solubility rules for ionic solids- 

Salts containing Group 1 elements (Li+,Na+,K+,Cs+,Rb+)are soluble . 

Salts containing nitrate ion (NO3-) are mostly soluble.

Salts containing Cl-, Br-, I-are generally soluble. However, halide salts of Ag+,Pb+,(Hg2)2+. Thus, AgCl, PbBr2, Hg2Cl2are insoluble.

Most silver salts are insoluble. AgNO3,Ag(C2H3O2) are exceptions.

Most sulfate salts are soluble, with few exceptions CaSO4, BaSO4,PbSO4,AgSO4,SrSO4 .

Most hydroxide salts are only slightly soluble, like the hydroxide salts of Group 2 elements (Ca, Sr, and Ba). But, The hydroxide salts of Group 1 elements are soluble.

Hydroxide salts of transition metals and Al3+ are insoluble. Thus, Fe(OH)3,Al(OH)2, Co(OH)2are not soluble.

Most of the sulfides of transition metals are highly insoluble.

Carbonates are frequently insoluble. 

Chromates are frequently insoluble. Examples include PbCrO4and BaCrO4

Phosphates like Ca3(PO4)2and Ag3PO4 are frequently insoluble.

Fluorides such as BaF2, MgF2and PbF2 are frequently insoluble.


Based on the solubility rules, which one of the following compounds should be insoluble in water?


a) Na2So4
b) CuSO4
c) BaSO4
d) MgSO4


Among the given options, BaSO4is insoluble in water. Most sulfate salts are soluble, but their are some exceptions like CaSO4, BaSO4,PbSO4,AgSO4,SrSO4 .


How to remember the solubility rules?


There are different ways to remember the solubility rules. One such way is using the pattern NAG SAG. Each letter represents soluble molecules.

N: Nitrates (NO3-)
A: Acetates (CH3COO-)
G: Group 1 alkali metals (Li+, Na+, etc)
S: Sulfates (SO4-2)
A: Ammonium ions (NH4+)
G: Group 17 nonmetals (F-, Cl-, Br-, I-, etc.)

Write PMS to represent the first exception. P stands for Pb+2 (lead). M stands for Mercury (Hg2+2). S stands for Silver (Ag+). These three ions are never soluble with sulfate group and group 17 nonmetals.

Write Castro Bear to represent the second exception. Castro Bear stands for Calcium (Ca+2), Strontium (Sr+2), and Barium (Ba+2). These three ions are not soluble with sulfates.


How do you use a solubility chart?


Solubility chart is a chart with a list of ions, representing what will be produced on combinations of different cations with anions and the solubility of the ions on mixing with each other.

Using a solubility chart the combination result of two different ions can be predicted. 


solubility table



Chemistry Questions Answers Pages


o2 lewis structure  coplanar OF2 lewis structure Formal charge formula n2 lewis structure

We Are Different from Others!

Help with Solubility Rules