The following are 7 examples of weak electrolytes:
- Hydrofluoric acid (HF)
- Hydrocyanic acid (HCN)
- Acetic acid (HC2H3O2)
- Nitrous acid (HNO2)
- Sulfurous acid (H2SO3)
- Chlorous acid (HClO2)
- Ammonia (NH3)
Explanation of Weak Electrolytes
Electrolytes are substances that, when dissolved in a solvent (like water), dissociate into ions and can conduct electrical current. However, electrolytes can be classified as strong or weak based on the extent to which they ionize or dissociate in solution.
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Strong Electrolytes: Dissociate almost completely into ions in solution. This results in a high concentration of ions, leading to strong electrical conductivity. Examples include strong acids (like hydrochloric acid - HCl), strong bases (like sodium hydroxide - NaOH), and soluble ionic compounds (like sodium chloride - NaCl).
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Weak Electrolytes: Dissociate only partially into ions in solution. This means that only a small fraction of the molecules break apart into ions, resulting in a lower concentration of ions compared to strong electrolytes. Consequently, they conduct electricity less effectively.
Why are these substances considered weak electrolytes?
The weak electrolytes listed above only partially ionize in water. For example:
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Acetic acid (HC2H3O2), a common weak acid, only a small percentage of the molecules donate a proton (H+) to water to form hydronium ions (H3O+) and acetate ions (C2H3O2-). The majority of the acetic acid molecules remain undissociated in solution.
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Ammonia (NH3), a weak base, only a small percentage of its molecules accept a proton from water to form ammonium ions (NH4+) and hydroxide ions (OH-). Most ammonia molecules remain unreacted in solution.
The degree of dissociation for a weak electrolyte is often quantified by its equilibrium constant (Ka for acids and Kb for bases). Lower Ka or Kb values indicate weaker electrolytes.
