Strong vs Weak Electrolytes
All the compounds can be categorized into two groups, as electrolytes and non-electrolytes based on their ability to produce ions and, therefore, able to conduct electricity. The process of passing a current through an electrolytic solution and, therefore, forcing the positive and negative ions to move towards their respective electrodes is called “electrolysis.” This process is carried out in an electrolytic cell. This concept is used in metal plating, isolation of solid-state elements or gases, in batteries, fuel cells, etc.
Electrolytes are present in our body too. They are needed to maintain the balance inside cells and blood fluids in a healthy body. Electrolyte balance is crucial to maintain the osmotic balance, hence the blood pressure inside the body. Na+, K+, Ca2+ are important in nerve impulse transmission and muscle contractions. Electrolyte homeostasis is controlled by various hormones in the body. For example, aldosterone, controls the Na+ amount. Calcitonin and parathormon hormones play a role to maintain the Ca2+ and PO43- balance. The electrolyte levels of the blood are measured to identify certain electrolyte imbalances. Mostly, Na+ and K+ levels in blood and urine are measured to check the kidney malfunctioning, etc. The normal Na+ level in blood is 135 – 145 mmol/L, and the normal K+ level is 3.5 – 5.0 mmol/L. Extreme levels of electrolytes in the body can be fatal. Electrolytes are also important in plant bodies. For example, the stomata opening and closing mechanisms by guard cells are controlled by electrolytes (K+).
Electrolytes are substances that produce ions. These compounds can produce ions when they are in molten stage or when they are dissolved in a solvent (water). Because of the ions, electrolytes can conduct electricity. Sometimes there may be solid-state electrolytes. Moreover, some gases like carbon dioxide produce ions (hydrogen and bicarbonate ions) when it is dissolved in water. There are two types of electrolytes, strong electrolytes and weak electrolytes.
Strong electrolytes readily produce ions when they are soluble. They completely dissociate to produce ions in a solution. For example, ionic compounds are strong electrolytes. Molten sodium chloride or aqueous NaCl solutions have completely dissociated into Na+ and Cl- ions; thus, they are good electricity conductors. Strong acids and bases are also good electrolytes.
Weak electrolytes produce few ions when they are soluble in water. They dissociate partially and produce few ions. In a solution of weak electrolytes, there will be dissociated ions as well as the neutral molecules of the substance. Therefore, the current conducted by such a solution is very low compared to a strong electrolytic solution. For instance, weak acids like acetic acid and weak bases are weak electrolytes.
What is the difference between Strong Electrolytes and Weak Electrolytes?
• Strong electrolytes readily dissolve in water, but weak electrolytes do not readily dissolve.
• Strong electrolytes completely dissociate or ionize in a solution, whereas a weak electrolyte partially dissociate or ionize.
• Strong electrolytes conduct electricity very efficiently due to a large number of ions in the medium, but weak electrolytes conduct only a small current.