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. S

    How to find the pH of HCl and NaOH combined.

    Homework Statement I have .100mL of .100M HCl titrated with .100M NaOH, Theres a chart I have to fill in and I'm completely lost. I have the volume of NaOH(from 0ml-200ml) I have to find the total volume of the solution, I get that, moles remaining of solution molarity of remaining solution...
  2. B

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  3. S

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  4. P

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  5. M

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  6. S

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  7. J

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  8. R

    PH to Concentration of Citric Acid

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  9. L

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  10. G

    Can Total Alkalinity and Carbonate Concentration Determine pH?

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  11. M

    Calculating pH of buffer after adding HCl

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  12. R

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  13. K

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  14. G

    Finding the pH of a buffered System

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  15. H

    Can Nitric Acid's pH be Increased to pH 10 with Water?

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  16. T

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  17. H

    Does pH Changing with Water & Acids Matter?

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  18. S

    Chemistry) Buffers and Ph differences question

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  19. K

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  20. M

    Chemistry - Concentration from known pH and Ka.

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  21. B

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  22. R

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  23. B

    What is the significance of pH in a basic solution?

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  24. T

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  25. M

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  26. J

    Simple questions on solutions concentration and pH

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  27. J

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  28. P

    C2H3O2- concentration given pH of 30mL NaC2H3O2 solution

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  29. B

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  30. B

    Calculating pH of the 1,96 % H3PO4 solution

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  31. V

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  32. K

    Copper Solubility in Water with pH 5

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  33. B

    Find the pH of a 10-7 mol l-1 H2CO3 Solution: Explained

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  34. Saitama

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  35. D

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  36. C

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  37. S

    Chemistry Find number of moles of HCl to change pH of Histidine buffer.

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  38. J

    Calculating Buffer Volumes for pH and Concentration Ratios

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  39. V

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  40. C

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  41. T

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  43. B

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  44. K

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  45. Q

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  46. M

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  47. R

    PH Scale: Understanding Its Mechanism

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  48. M

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  49. Y

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  50. N

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