What is Ph: Definition and 520 Discussions

In chemistry, pH (, denoting 'potential of hydrogen' or 'power of hydrogen') is a scale used to specify the acidity or basicity of an aqueous solution. Acidic solutions (solutions with higher concentrations of H+ ions) are measured to have lower pH values than basic or alkaline solutions.
The pH scale is logarithmic and inversely indicates the concentration of hydrogen ions in the solution. This is because the formula used to calculate pH approximates the negative of the base 10 logarithm of the molar concentration of hydrogen ions in the solution. More precisely, pH is the negative of the base 10 logarithm of the activity of the H+ ion.At 25 °C, solutions with a pH less than 7 are acidic, and solutions with a pH greater than 7 are basic. Solutions with a pH of 7 at this temperature are neutral (e.g. pure water). The neutral value of the pH depends on the temperature – being lower than 7 if the temperature increases. The pH value can be less than 0 for very strong acids, or greater than 14 for very strong bases.The pH scale is traceable to a set of standard solutions whose pH is established by international agreement. Primary pH standard values are determined using a concentration cell with transference, by measuring the potential difference between a hydrogen electrode and a standard electrode such as the silver chloride electrode. The pH of aqueous solutions can be measured with a glass electrode and a pH meter, or a color-changing indicator. Measurements of pH are important in chemistry, agronomy, medicine, water treatment, and many other applications.

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  1. C

    PH rising during ammonia extraction with evaporation

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  2. J

    Understanding pH: Number of Ions in H+ & OH-

    Although the masses of a mole of H+ and a mole of OH- are different, what is the number of ions contained in each?
  3. R

    Finding pH of solution knowing E°....

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  4. I

    Correlation Between pH & Electrolysis Rate

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  5. D

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  6. F

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  7. J

    Find the Error: Calculating pH of 0.5L Diluted HA Solution

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  8. N

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  9. xyla

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  10. T

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  11. C

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  12. F

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  13. T

    Buffer Solution Calculation Example

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  14. J

    Physical Chemistry pH question

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  15. Teemo

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  16. M

    Electrochemical Cells (involving partial pressures and pH)

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  17. schrodingerscat11

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  18. T

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  19. C

    Understanding Changes in Tap Water pH Over Time

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  20. C

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  21. C

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  22. C

    Ph Scale Logarithms: Calculating Acidity Difference

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  23. J

    Predict whether the following is neutral, basic, or acidic and the pH

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  24. K

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  25. Jason49

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  26. F

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  27. R

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  28. Q

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  29. Y

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  30. A

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  31. Y

    Electrochemistry pH in solution cell

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  32. QuantumCurt

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  33. Q

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  34. Ritzycat

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  35. D

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  36. M

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  37. J

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  38. R

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  39. S

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  40. S

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  41. N

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  42. Q

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  43. K

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  44. B

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  45. Q

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  46. A

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  47. Q

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  48. J

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  49. C

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  50. Y

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