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pH of Water and Marine Lives

Last updated over 2 years ago
3 questions
pH is a determined value based on a defined scale. It is a figure between 0 and 14 defining how acidic or basic a body of water is along a logarithmic scale ¹. The lower the number, the more acidic the water is. The higher the number, the more basic it is. A pH of 7 is considered neutral. The logarithmic scale means that each number below 7 is 10 times more acidic than the previous number when counting down. Likewise, when counting up above 7, each number is 10 times more basic than the previous number.

pH stands for the “power of hydrogen” ³. The numerical value of pH is determined by the molar concentration of hydrogen ions (H+) ³. This determination is due to the effect of hydrogen ions (H+) and hydroxyl ions (OH-) on pH. The higher the H+ concentration, the lower the pH, and the higher the OH- concentration, the higher the pH. At a neutral pH of 7 (pure water), the concentration of both H+ ions and OH- ions is 10⁻⁷ M. Due to this influence, H+ and OH- are related to the basic definitions of acids and bases.

In the whiteboard below label the pH scale to show the acidic, basic and neutral pH. Use the T button on the left to add your labels.
1

Label the pH Scale with the following. Acid/Base/Neutral/More OH-/More H+/OH-=H+

1

Any molecule that has a high concentration of hydroxyl ions [ OH-]are considered

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Any molecule that has a high concentration of hydrogen ions [ H+]are considered