Objective
- Classify the solutions to whether the electrolyte or the non-electrolyte as a pair of electrodes immerse into the solutions and we observe the brightness of light bulb.
Introduction
- Liquids and solution can be classified according to substances that contained. The substances are divided to two types. When the substances dissolve in a solvent, such as water, if they cause liquids to conduct electricity, they ard called electrolytes. Because the substances have two parts of charged ions which a cation that is positively charged and an anion that is negatively charged, when they are dissolve in water, they ionize in water, and eventually, the liquids change to electrically conductive. For example, when NaCl is dissolved in water, the bond between the Na+ and Cl- ions breaks down and then it is totally ionized. The solution process can be represented as:
NaCl(s) + H2O(l) → Na+(aq)+ Cl-(aq)
Therefore, NaCl is called strong electrolyte, and it is an example of ionization of ionic compounds which ionize easily in solution.
All strong acids and bases dissociate completely into ions in solution. If a covalent compound, such as HCl (g) which is strong acid is dissolved in water, it is represented as :
HCl(g) + H2 O(l) → H3O + (aq)+ Cl-(aq)
As a result, positive hydronium ions and negative chloride ions ard produced in sufficient quantity to make hydrochloric acid conductive, and a large fraction of the HCl dissolved in water is ionized, producing a large amount of electricty carrying ions. There is also strong base NaOH which is 100% ionized in water and it is represented as :
NaOH(s)+H2O → Na+(aq)+OH-(a)
For this reason, those strong acid and base are totally ionized in water, and the solution can conduct electricity. Therefore, they are called strong electrolytes.
However, there are also weak acidic and base which called weak electrolytes. For example, when NH3 which is weak base is dissolved in water, it can be...