Acids are chemicals that release H+ ions when they get dissolved in water. Acids are typically corrosive, taste sour, and would turn a litmus paper red. An example of an acidic substance is vinegar, as it contains a percentage of acetic acid. There are two types of acids: strong acids and weak acids. Strong acids fully ionize in water, while weak acids only partially ionize. There are 7 strong acids, namely sulfuric acid, nitric acid, hydrobromic acid, hydroiodic acid, hydrochloric acid, chloric acid, and perchloric acid. Bases, on the other hand, are chemicals that release OH- ions when they get dissolved in water. Bases are slippery, taste bitter, and would turn a litmus paper blue. An example of a basic substance is baking soda, which is made of sodium bicarbonate. There are also two types of bases: strong bases and weak bases. Strong bases fully ionize in water, while weak bases only partially ionize. There are 8 strong bases, which cations come from groups I and II of the periodic table: lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, calcium hydroxide, strontium hydroxide, and barium hydroxide. The pH scale is a scale to measure the acidity of a substance. The scale ranges from 0 to 14, the lower the number, the more acidic it is, and the higher the number, the more basic it is. The pH of a substance is measured with the formula pH = -log[H+]. Meanwhile, the pOH of a substance is measured with the formula pOH = -log[OH-]. The square brackets here represent molarity. The pH and pOH of a substance will add up to the pKw – the negative log of the ion product of water – which is equal to 14 at room temperature.
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