The pH scale is a measurement of how acidic a solution is or how alkaline it is. It has a range of 14 units, which pH 1 being the most acidic and pH 14 being the most alkaline. Common acids include vinegar and lemon juice, which are about pH 3; common alkalis include sodium bicarbonate, which is about pH 11.
A pH of below 6 is regarded as acid with 6 being a very weak acid and pH 1 being the strongest acid. This is the pH of something like hydrochloric acid. A pH of around 7 (6 to 8) is regarded as neutral – this is the pH of ordinary tap water. A pH of 8-14 is regarded as alkaline with pH 14 being the pH of a very concentrated solution of sodium hydroxide.
The pH of a solution can be measured on the pH scale using indicators. These include litmus, which can be impregnated into paper, giving an easily dip reaction. The paper changes colour and this can then be compared with the colours on a known pH scale.
A pH of below 6 is regarded as acid with 6 being a very weak acid and pH 1 being the strongest acid. This is the pH of something like hydrochloric acid. A pH of around 7 (6 to 8) is regarded as neutral – this is the pH of ordinary tap water. A pH of 8-14 is regarded as alkaline with pH 14 being the pH of a very concentrated solution of sodium hydroxide.
The pH of a solution can be measured on the pH scale using indicators. These include litmus, which can be impregnated into paper, giving an easily dip reaction. The paper changes colour and this can then be compared with the colours on a known pH scale.
