Ch.4 - Chemical Quantities & Aqueous ReactionsSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

Electrolytes are compounds that can conduct electricity once they are dissolved in a solvent. 

Understanding Electrolytes

Concept #1: The Classification of Electrolytes

Whenever you add a solute to a solvent there are three possible outcomes: the solute dissolves completely, dissolves partially or doesn't dissolve at all into ions. 

Concept #2: The Strong Electrolytes

Strong Electrolytes break up into ions completely and are grouped into 3 categories: Strong Acids, Strong Bases and Soluble Ionic Compounds

Concept #3: The Weak Electrolytes

Weak Electrolytes partially break up into ions and are grouped into 2 categories: Weak Acids and Weak Bases

Concept #4: The Non-Electrolytes

Non-Electrolytes do NOT break up into ions at all and are commonly referred to as molecular compounds

Example #1: Each of the following reactions depicts a solute dissolving in water. Classify each solute as a strong electrolyte, a weak electrolyte or a non-electrolyte. 

a.  PbSO4 (s) → PbSO4 (aq) 

b.  HC2H3O2 (aq)  ⇌  H+ (aq) + C2H3O2 (aq)

c.  CaS (s) → Ca2+(aq) + S2- (aq)

d.  Hg (l) → Hg (aq)

Based on different classifications of electrolytes we can expand to other compounds. 

Practice: Classify each of the following solutes as either a strong electrolyte, a weak electrolyte or a non-electrolyte.

a. Perbromic acid, HBrO4

b. Lithium chloride, LiCl

c. Formic Acid, HCO2H

d. Methylamine, CH3NH2

e. Zinc bromide, ZnBr2

f. Propanol, C3H8OH


Additional Problems
Which of the following compounds is a non-electrolyte? A. NaCl B. Na2CO3 C. KBr D. C2H6O E. HCl
Which of the following water soluble compounds does not conduct an appreciable current in aqueous solution by means of ion movement ? a. CH3COOH (acetic acid) b. NaNO3 c. CH3CH2OH (ethyl alcohol) d. KCl e. HF
Choose the statement below that is TRUE. A. A molecular compound that does not ionize in solution is considered a strong electrolyte. B. A strong acid solution consists of only partially ionized acid molecules. C. A weak acid solution consists of mostly non-ionized (or non-dissociated) acid molecules. D. The term "weak electrolyte" means that the substance is inert. E. The term "strong electrolyte" means that the substance is extremely reactive.
Which of the following is considered a STRONG electrolyte? A. CH3SH B. NH4NO3 C. C12H22O11 D. HC2H3O2 E. all of the above
Which of the following is a weak electrolyte in aqueous solution? a) HF b) NaF c) HCl d) KCl
Which of the following are strong electrolytes? i) HBr ii) HC2H3O2 iii) NH3 iv) KNO3 a) i, iv b) i, iii, iv c) i, ii, iii, iv d) i, ii, iv e) ii, iv
HCl, KOH,LiCl, and KI are ALL classified as       A) nonelectrolytes.      B) weak electrolytes.              C) strong electrolytes.      D) acids.
Which of the following is a strong electrolyte?      A) CH4            B) NH4NO3     C) H2O            D) CH3OH                  E) CCl4
Which of the following is considered a STRONG electrolyte? a) NH4NO3 b) C12H22O11 c) PbBr2 d) HC2H3O2 e) CH3SH
HCl, HI, H2SO4, LiCl, and KI are all classified as       A) nonelectrolytes      B) weak electrolytes               C) strong electrolytes              D) strong acids
Three different substances, A2X, A2Y, and A2Z, were dissolved in water with the following results. (Water molecules are omitted for clarity.) Which is the strongest electrolyte, and which is the weakest?
Which of the following aqueous solutions is a nonelectrolyte? A. HF B. NaClO4 C. C12H22O11 D. NH3 E. FeCl3
Which of the following is a weak electrolyte? 1. CaCl2(aq)           2. HNO3(aq)          3. C2H6O(aq)          4. H3PO4(aq)
Which of the following is both a weak acid and a weak electrolyte? A. HF B. NH3 C. CH3OH D. HCl  E. HNO3
Which of these compounds is a strong electrolyte? A)  H2O B)  O2                     C)  H2SO4              D)  C6H12O6 (glucose)      E)  CH3COOH (acetic acid)
Potassium phosphate, K3PO4, sodium iodide, Nal, magnesium chloride, MgCl 2, methanol, CH3OH, and ammonium chloride, NH4Cl, are soluble in water. Which would be the strongest electrolyte per mole of dissolved solute? a) K3PO4 b) Nal c) MgCl2 d) CH3OH e) NH4Cl
Which of the following is  NOT a strong electrolyte? a) LiOH        b) CaCl2        c) MgCO3        d) NaC2H3O2         e) Li2SO4
Which of the following is considered a STRONG electrolyte? a) NH4NO3    b) C12H22O11        c) PbCl2        d) HC2H3O2        e) CH3OH
Which of the following statements is/are correct?  a)    Nitric acid is a weak electrolyte b)    Strontium hydroxide is a strong electrolyte c)    CH3CH2OH  is a weak electrolyte d)    NaCl is a non-electrolyte e)    Hydrobromic acid is a weak electrolyte
The dissolution of a compound is given by the reaction below:  Identify each of the following solutions as either electrolytic, weakly electrolytic or non-electrolytic. 
Which one of the following compounds is a nonelectrolyte when dissolved in water? a) calcium chloride (CaCl2) b) potassium hydroxide (KOH) c) sodium acetate (NaCH3CO2) d) acetic acid (CH3CO2H) e) glucose (C6H12O6)
Salts may be either strong or weak electrolytes. Which of the following is considered to be the salt? a) HF b) C12H22O11 c) AgBr d) HC2H3O2 e) HBrO
Which of the following is a strong electrolyte? A. Glucose (C12H22O11) B. Acetic acid (HC2H3O2) C. Methane (CH4) D. Hydrochloric acid (HCl)
Which of the following compounds is a weak acid, or weak electrolyte? a) HI b) HCl c) CH3CO2H d) HClO4 e) HNO3
Electrolyte Classifications
Which of the following aqueous solutions would not conduct electricity at all? a) HNO3 b) CaCl2 c) H2CO d) KOH e) H3PO4
Which of the following is a weak electrolyte?             a) HBr            b) KOH          c) CH3OH                  d) RbOH        e) HF
Explain how a strong electrolyte, a weak electrolyte, and a nonelectrolyte differ.
Which of the following is a strong electrolyte? A. Glucose (C12H22O11) B. Acetic acid (HC2H3O2)  C. Methane (CH4)  D. Hydrochloric acid (HCI) 
Partial ionization is associated with which of the following? A. Strong acids B. Nonelectrolytes C. Weak acids D. Strong electrolytes
Identify each of the following substances as strong electrolyte, weak electrolyte, or nonelectrolyte: A) Ba(NO3)2, B) Ne, C) NH3, D) NaOH,
Which of the following is not a weak electrolyte? a. CH3COOH b. HF c. NH3 d. HNO3 e. all these are weak electrolytes
Which of the following statements is/are INCORRECT?1. Water soluble ionic compounds, such as NaCl, are all strong electrolytes.2. Some acids are strong acids while others are weak.  The acids HF and HNO2 are examples of strong acids.3. Only Group 1 (1A) hydroxides are soluble in water. a. 1 and 2 onlyb. 2 and 3 onlyc. 1 and 3 onlyd. 1 only or 2 only or 3 onlye. 1, 2, and 3 
Which of the following statement(s) is/are correct?    i. KBr, HI, and Mg(OH) 2 are strong electrolytes    ii. NaH, CH 3COOH, and NH3 are weak electrolytes    iii. C3H7OH, C6H11O6, and O2 are non-electrolytes A) i only B) ii only C) iii only D) i and ii E) i and iii
In a sugar solution, molecules dissolve as __ . A. individual ionsB. intact moleculesC. strong electrolytesD. redox components
Which of the following are not electrolytes: a. Li2S b. BaCl2 c. K2C2O4 d. C3H8O3 e. SrSO4
Differentiate between what happens when the following are dissolved in water.d. HNO3 versus CO
Which of the following statements is(are) true? For the false statements, correct them.a. A concentrated solution in water will always contain a strong or weak electrolyte.
Which of the following statements is(are) true? For the false statements, correct them.b. A strong electrolyte will break up into ions when dissolved in water.
Which of the following statements is(are) true? For the false statements, correct them.c. An acid is a strong electrolyte.
Which of the following schematic drawings best describes a solution of Li2SO4 in water (water molecules not shown for simplicity)?
Methanol, CH3OH, and hydrogen chloride, HCl, are both molecular substances, yet an aqueous solution of methanol does not conduct an electrical current, whereas a solution of HCl does conduct. Account for this difference.
Which of the following statements is(are) true? For the false statements, correct them.d. All ionic compounds are strong electrolytes in water.
A 0.1 M solution of acetic acid, CH3COOH, causes the lightbulb in the apparatus of Figure 4.2 to glow about as brightly as a 0.001 M solution of HBr. How do you account for this fact?
You are presented with three white solids, A, B, and C, which are glucose (a sugar substance), NaOH, and AgBr. Solid A dissolves in water to form a conducting solution. B is not soluble in water. C dissolves in water to form a nonconducting solution. Identify A, B, and C.
When 1.0 mol of solid lead nitrate is added to 2.0 mol of aqueous potassium iodide, a yellow precipitate forms. After the precipitate settles to the bottom, does the solution above the precipitate conduct electricity? Explain. Write the complete ionic equation to help you answer this question.
Which of the following statements is (are) true? For the false statements, correct them.a. A concentrated solution in water will always contain a strong or weak electrolyte.
Which of the following statements is (are) true? For the false statements, correct them.b. A strong electrolyte will break up into ions when dissolved in water.
Which of the following statements is (are) true? For the false statements, correct them.c. An acid is a strong electrolyte.
Which of the following statements is (are) true? For the false statements, correct them.d. All ionic compounds are strong electrolytes in water.
When asked what causes electrolyte solutions to conduct electricity, a student responds that it is due to the movement of electrons through the solution. Is the student correct? If not, what is the correct response?
Classify these compounds as strong electrolytes, weak electrolytes, or nonelectrolytes. H2SO4, (NH4)2S, HClO
Ammonium hydroxide is a weak base becausea. it is a dilute solutionb. It is not soluble in waterc. it cannot hold on to its hydroxide ionsd. it dissociates only slightly in watere. it is completely ionized in aqueous solution 
Which of the following aqueous solutions is a nonelectrolyte? A. HFB. NaClO4 C. C12H22O11 D. NH3E. FeCl3
Indicate the concentration of each ion or molecule present in the following solutions: (c) 0.0150 M C6H12O6Assume that the volumes are additive.
Show how each of the following strong electrolytes “breaks up” into its component ions upon dissolving in water by drawing molecular-level pictures.a. NaBr
Which of the following solutions will have the highest electrical conductivity?A) 0.045 M Al 2(SO4)3B) 0.050 M (NH 4)2CO3C) 0.10 M LiBrD) 0.10 M NaIE) 0.10 M KF
What is the non-electrolyte among the set? a) NaCl b) CH3CH2CH2OH c) LiOH d) BaCl2 e) K2O2
Which of the following aqueous solutions would be a strong electrolyte: a. HBrO b. HF c. NH3 d. C6H6O e. HCI
Classify these compounds as strong electrolytes, weak electrolytes, or nonelectrolytes. HBr, FeCl2, H2CO3
In water, a substance that ionizes completely in solution is called a:a. electrolyteb. weak electrolytec. nonconductord. nonelectrolyte 
What is the difference between (b) a weak acid and a strong acid
What is the difference between (c) an acid and a base?
Which of the following would be a strong electrolyte: i. KCIO3 ii. HI iii. HC2H3O2 A. i only B. iii only C. i and ii D. i and iii E. ii and iii
Which of the following statements is TRUE?a. Ionic compounds at room temperature typically conduct electricity.b. An ionic bond is formed through the sharing of electrons.c. An ionic bond is generally formed between a metal and a nonmetal.d. Once dissolved in water, ionic compounds rarely conduct electricity.e. None of the above are true.
Classify these compounds as strong electrolytes, weak electrolytes, or nonelectrolytes. AgClO3  NH3  Fe(OH)2  NaOH H2SO4  HClO HNO2  HCl Zn(NO3)2
HO, HBr, and HI are strong acids, yet HF is a weak acid. What does this mean in terms of the extent to which these substances are ionized in solution?
Label each of the following substances as an acid, base, salt, or none of the above. Indicate whether the substance exists in aqueous solution entirely in molecular form, entirely as ions, or as a mixture of molecules and ions. (a) HF
Label each of the following substances as an acid, base, salt, or none of the above. Indicate whether the substance exists in aqueous solution entirely in molecular form, entirely as ions, or as a mixture of molecules and ions. (b) acetonitrile, CH3CN
Label each of the following substances as an acid, base, salt, or none of the above. Indicate whether the substance exists in aqueous solution entirely in molecular form, entirely as ions, or as a mixture of molecules and ions. (c) NaClO4
Label each of the following substances as an acid, base, salt, or none of the above. Indicate whether the substance exists in aqueous solution entirely in molecular form, entirely as ions, or as a mixture of molecules and ions. (d) Ba(OH)2
An aqueous solution of an unknown solute is tested with litmus paper and found to be acidic. The solution is weakly conducting compared with a solution of NaCl of the same concentration. Which of the following substances could the unknown be: KOH, NH3, HNO3, KClO2, H3PO3, CH3COCH3 (acetone)?
Classify each of the following substances as a nonelectrolyte, weak electrolyte, or strong electrolyte in water: (a) H2SO3
Classify each of the following substances as a nonelectrolyte, weak electrolyte, or strong electrolyte in water: (b) C2H5OH (ethanol)
Classify each of the following substances as a nonelectrolyte, weak electrolyte, or strong electrolyte in water: (c) NH3
Classify each of the following substances as a nonelectrolyte, weak electrolyte, or strong electrolyte in water: (d) KClO3
Classify each of the following substances as a nonelectrolyte, weak electrolyte, or strong electrolyte in water: (e) Cu(NO3)2.
Which of the following is a soluble, strong base?a. Sr(OH)2b. NH2OHc. Fe(OH)3d. Cr(OH)3e. Be(OH)2
Classify each of the following aqueous solutions as a nonelectrolyte, weak electrolyte, or strong electrolyte: (a) HClO4
Classify each of the following aqueous solutions as a nonelectrolyte, weak electrolyte, or strong electrolyte: (b) HNO3
Classify each of the following aqueous solutions as a nonelectrolyte, weak electrolyte, or strong electrolyte: (c) NH4Cl
Classify each of the following aqueous solutions as a nonelectrolyte, weak electrolyte, or strong electrolyte: (d) CH3COCH3 (acetone) 
Classify each of the following aqueous solutions as a nonelectrolyte, weak electrolyte, or strong electrolyte: (e) CoSO4
Classify each of the following aqueous solutions as a nonelectrolyte, weak electrolyte, or strong electrolyte: (f) C12H22O11 (sucrose).
A solution containing an electrolytea. conducts electricity. b. does not conduct electricity. c. produces gas.d. is insoluble.
Classify these compounds as strong electrolytes, weak electrolytes, or nonelectrolytes.  HBr, H2CO3, FeCI2
Which compound is an electrolyte?a. C6H12O6b. C12H22O11c. CH3CH2OHd. CH3COOH 
Classify each of the following as a strong electrolyte or non electrolyte. MgBr2, C12H22O11, Na2CO3, KOH
K2SO4 is a strong electrolyte. Determine the concentration of each of the individual ions in a 0.650 M K2SO4 solution. [K+] = [SO42-] =