The Characteristic Properties of Acids and Bases

Section 1: Characteristic Properties of Acids

Acids are substances that possess a sour taste and primarily react with bases to form salts and water.
They also turn blue litmus paper red, indicating their acidic nature.
Acids contain a certain concentration of hydrogen ions (H+) when dissolved in water. This is what distinguishes them as acids.
They have a pH value lower than 7, with a 1 being very acidic and a 7 being neutral.
Acids can be identified through acid-base reactions, which often produce heat, also known as exothermic reactions.
Strong acids such as hydrochloric acid (HCl), sulphuric acid (H2SO4), and nitric acid (HNO3) are corrosive and when in high concentrations can cause skin burns.
When acids react with metals, they tend to discharge hydrogen gas. This can be represented by the general equation: Acid + Metal → Salt + Hydrogen gas

Section 2: Characteristic Properties of Bases

Bases are bitter in taste and are substances which react with acids to form salts and water.
A base gives hydroxide ions (OH-) when dissolved in water, which makes them a base.
They turn red litmus paper blue which indicates their basic (alkaline) nature.
Bases have a pH value higher than 7, with 14 being very basic or alkaline, and 7 being neutral.
Bases can be recognized by acid-base reactions and the sort of salts they form with acids.
Strong bases or alkalis such as sodium hydroxide (NaOH) and potassium hydroxide (KOH) can also cause skin burns.
Bases that are soluble in water are known as alkalis.
Important to note, not all bases are soluble, but all alkalis are bases.