pHväärtus

pHväärtus, often shortened to pH, is a scale used to specify the acidity or basicity of an aqueous solution. The scale typically ranges from 0 to 14. A pH value of 7 is considered neutral. Solutions with a pH less than 7 are acidic, and solutions with a pH greater than 7 are alkaline or basic. The pHväärtus is defined as the negative base-10 logarithm of the hydrogen ion concentration. Mathematically, it is expressed as pH = -log10[H+]. A lower pH value indicates a higher concentration of hydrogen ions, and thus greater acidity. Conversely, a higher pH value signifies a lower concentration of hydrogen ions and greater alkalinity. Common examples include pure water with a neutral pH of 7, lemon juice which is acidic with a pH around 2, and household ammonia which is alkaline with a pH around 11. The pHväärtus is a crucial measurement in many scientific fields, including chemistry, biology, environmental science, and agriculture, as it influences chemical reactions, biological processes, and the behavior of substances in water.