NaOH in presence of water produces OH - ion. Youtube - Hindi. Show Topics Topics Introduction Reaction of metals with acids Reaction of metals with bases Reaction of metal carbonates and metal hydrogen carbonates w Reaction of metallic oxides with acids Reaction of non-metallic oxides with base Reaction of acids and bases What happens to acid and base in water Cautions while adding acid to water Acid and bases conduct electricity pH scale pH scale in our day to day life Chemicals from salt Sodium hydroxide Bleaching powder Baking soda Washing soda Water of crystallisation.
Class 10 Chemistry Acids Bases Salts Acid and bases conduct electricity Acid and bases conduct electricity Acids and Bases exhibit their conducting property only if they are in aqueous solution in which they could completely ionize in water. The reaction is as follows: Base when dissolved in water produces OH - ion. Class 10 Chemistry Acids Bases Salts. The terms strong and weak describe the ability of acid and base solutions to conduct electricity.
If the acid or base conducts electricity strongly, it is a strong acid or base. If the acid or base conducts electricity weakly, it is a weak acid or base. The instructor will test the conductivity of various solutions with a light bulb apparatus.
The light bulb circuit is incomplete. If the circuit is completed by a solution containing a large number of ions, the light bulb will glow brightly indicating a strong ability to conduct electricity as shown for HCl. If the circuit is completed by a solution containing large numbers of molecules and either no ions or few ions, the solution does not conduct or conducts very weakly as shown for acetic acid.
An acid or base which strongly conducts electricity contains a large number of ions and is called a strong acid or base and an acid or base which conducts electricity only weakly contains only a few ions and is called a weak acid or base.
The bond strengths of acids and bases are implied by the relative amounts of molecules and ions present in solution.
The bonds are represented as:. Acids or bases with strong bonds exist predominately as molecules in solutions and are called "weak" acids or bases. Acids or bases with weak bonds easily dissociate into ions and are called "strong" acids or bases.
Acids and bases behave differently in solution based on their strength. Acid or base "strength" is a measure of how readily the molecule ionizes in water. Some acids and bases ionize rapidly and almost completely in solution; these are called strong acids and strong bases. For example, hydrochloric acid HCl is a strong acid.
A similar concept applies to bases, except the reaction is different. A strong base like sodium hydroxide NaOH will also dissociate completely into water; if you put in 1 mole of NaOH into water, you will get 1 mole of hydroxide ions. The terms "strong" and "weak" in this context do not relate to how corrosive or caustic the substance is, but only its capability to ionize in water. The ability of a substance to eat through other materials or damage skin is more of a function of the properties of that acid, as well as its concentration.
Although, strong acids are more directly dangerous at lower concentrations a strong acid is not necessarily more dangerous than a weak one. For example, hydrofluoric acid is a weak acid 1 , but it is extremely dangerous and should be handled with great care. Hydrofluoric acid is particularly dangerous because it is capable of eating through glass, as seen in the video in the links section V1.
The percent dissociation of an acid or base is mathematically indicated by the acid ionization constant K a or the base ionization constant K b 1. These terms refer to the ratio of reactants to products in equilibrium when the acid or base reacts with water. For acids the expression will be. The stronger an acid is, the lower the pH it will produce in solution. For strong acids, you can calculate the pH by simply taking the negative logarithm of its molarity as it completely dissociates into its conjugate base and hydronium.
The same goes for strong bases, except the negative logarithm gives you the pOH as opposed to the pH.
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