pHscale

The pH scale is a vital measuring tool used in areas such as medicine, biology, chemistry, agriculture, forestry, food science, environmental science, oceanography, civil engineering and many other applications. The scale provides an indicator as to the acidity or alkalinity of the measured solution. For example this information can be used to calculate the health of a water system as anything above or below optimum acidity of a natural river can affect nutrient uptake by plants and cause stress to organisms. The pH scale is physically measured by using pH indicator paper which turns a specific colour according to the level of acidity/alkalinity. I do believe the pH scale is a little arbitrary as the decision of scale from 0-14 is not based on any system. The application of a particular colour in relation to the number on the scale (e.g. the colour of the indicator paper is a certain green according to this persons interpretation) is also subjective. The pH scale is an interesting example of a measureing system which we rely on form day to day but seems to have appeared out of nowhere?

Ben Paul