What is a Buffer Solution?
Some solutions resist changes in pH when small amounts of acid or base are added. On addition of acid the hydrogen ions get removed by one of the components of the mixture and on addition of base the hydroxide ions get removed by one of the components of the mixture. The effect is called buffering action an solutions that behave this way are called buffers. It must be remembered at this point that pH is a measure of the concentration of H+ ions. Also that the product of H+ ion and OH- ion concentrations is always constant (at constant temperature) and equal to 1 x 10-14 [H+] x [OH-] = 1 x 10-14 mol2 dm-6 There are two types of buffer. • Weak acid and the salt of the same weak acid, (for example a solution containing ethanoic acid and sodium ethanoate). This gives a buffer solution with a pH less than 7 • Weak base and the salt of a the same weak base (for example ammonia and ammonium chloride solution). This gives a buffer with a pH greater than 7 The first (acidic) buffer works in the
A buffer solution is water mixed with a chemical to give it special properties in regards to pH (acidity). The chemical, known as a buffer agent, resists pH changes when exposed to acids and bases when properly mixed in a solution. This property makes a buffer solution extremely useful in protecting sensitive equipment, dealing with chemical accidents, and even in balancing the internal processes of living things. A buffer solution is made by mixing a buffer agent’s acid form (HA) with its conjugate base (A-) in water. Once a balance exists between HA and A-, any other acids or bases added to the buffer solution will be neutralized when they turn a portion of the buffer agent into either the HA or A- form. The change in the buffer agent initially causes little change in the buffer solution’s pH. As the proportion of a buffer agent’s HA and A- changes due to the addition of other acids and bases, the buffering capacity of the solution decreases. Eventually, a buffer agent can be used up
Definition A buffer solution is one which resists changes in pH when small quantities of an acid or an alkali are added to it. Acidic buffer solutions An acidic buffer solution is simply one which has a pH less than 7. Acidic buffer solutions are commonly made from a weak acid and one of its salts – often a sodium salt. A common example would be a mixture of ethanoic acid and sodium ethanoate in solution. In this case, if the solution contained equal molar concentrations of both the acid and the salt, it would have a pH of 4.76. It wouldn’t matter what the concentrations were, as long as they were the same. You can change the pH of the buffer solution by changing the ratio of acid to salt, or by choosing a different acid and one of its salts.
