Acids and bases are encountered often both in day to day living and in chemistry. They have opposite properties and possess the ability to cancel or neutralize one another. Acids and bases are carefully controlled in the body by the blood, lungs and kidneys via equilibrium processes.
Taste sour. Taste bitter.
Give sharp stinging pain in a cut or wound. Feels slippery
Turn blue litmus paper red. Turn red litmus paper blue.
Turn phenolphthalein colorless. Turn phenolphthalein pink.
React with metals to produce hydrogen gas.
React with carbonates or bicarbonates to produce carbon dioxide gas.
The definition of acids and bases involving hydroxide ions and hydrogen, respectively is too much limiting. A wider definition was suggested by Lowry and Bronsted in 1923. The key effect of the definition is to improve the number of substances that behave as bases.
In chemistry, acids and bases have been described differently through three sets of theories. The first is the Arrhenius definition, which revolves round the idea that acids are substances which ionize (break off) in an aqueous solution to make hydrogen (H+) ions while bases create hydroxide (OH-) ions in solution. However, the Bronsted-Lowry definition identifies acids like substances that give protons (H+) whereas bases tend to be substances that accept protons. Additionally, the Lewis theory of acids and bases says that acids are electron pair acceptors although bases are electron pair donors. Acids and bases could be defined by their chemical and physical observations.
Acids and bases are normal solutions that you can get everywhere. Almost every fluid that we come across in our everyday lives consists of acidic and basic properties, with the exception of water. They have totally different properties and are capable of neutralize to make H2O, which will probably be discussed afterwards in a subsection. Examples of acids and bases: Soap, bleach, toothpaste, limewater, cleaning agents, sodium hydroxide and ammonia water.
Acids and bases are present as conjugate acid-base sets. The word conjugate originates from the Latin stems meaning joined together and describes things that are joined, particularly in pairs, including Brnsted acids and bases.
Every time a Brnsted acid functions as an H+-ion donor, it forms a conjugate base. Imagine a generic acid, HA. Once this acid donates an H+ ion to water, one item of the response is the A- ion, which is a Brnsted base or hydrogen-ion acceptor.
Conversely, each time a base gains an H+ ion, the item is a Brnsted acid, HA. Acids and bases within the Brnsted model therefore are present as conjugate sets whose formulas are related by the loss or gain of a hydrogen ion.
Typical Brnsted Acids and Their Conjugate Bases