what is universal indicator give some example
Answers
Answered by
4
A universal indicator is a pH indicator composed of a solution of several compounds that exhibits several smooth colour changes over a pH value range from 0 to 14 (it may be negative or higher depending on the concentration) to indicate the acidity or alkalinity of solutions, where 7 indicates neutral. Although there are several commercially available universal pH indicators, most are a variation of a formula patented by Yamada in 1933.[1] Details of this patent can be found in Chemical Abstracts.[2] Experiments with Yamada's universal indicator are also described in the Journal of Chemical Education.[3]
A universal indicator is typically composed of water, propan-1-ol, phenolphthalein sodium salt, sodium hydroxide, methyl red, bromothymol blue monosodium salt, and thymol blue monosodium salt.[4] The colours that indicate the pH of a solution, after adding a universal indicator, are:
pH rangeDescriptionColour< 3Strong acidRed3–6Weak acidOrange or yellow7NeutralGreen8–11Weak baseBlue> 11Strong baseViolet or Indigo
The colours from yellow to red indicate an acidic solution, colours blue to violet indicate bases and green colour indicates that a solution is neutral.
Universal indicator componentsIndicatorLow pH colourTransition pH rangeHigh pH colourThymol blue (first transition)Red1.2 – 2.8YellowMethyl redRed4.4 – 6.2YellowBromothymol blueYellow6.0 – 7.6BlueThymol blue (second transition)Yellow8.0 – 9.6BluePhenolphthaleinColourless8.3 – 10.0Fuchsia
Wide-range pH test papers with distinct colours for each pH from 1 to 14 are also available. Colour matching charts are supplied with the specific test strips purchased.
pls mark my answer as brainliest
A universal indicator is typically composed of water, propan-1-ol, phenolphthalein sodium salt, sodium hydroxide, methyl red, bromothymol blue monosodium salt, and thymol blue monosodium salt.[4] The colours that indicate the pH of a solution, after adding a universal indicator, are:
pH rangeDescriptionColour< 3Strong acidRed3–6Weak acidOrange or yellow7NeutralGreen8–11Weak baseBlue> 11Strong baseViolet or Indigo
The colours from yellow to red indicate an acidic solution, colours blue to violet indicate bases and green colour indicates that a solution is neutral.
Universal indicator componentsIndicatorLow pH colourTransition pH rangeHigh pH colourThymol blue (first transition)Red1.2 – 2.8YellowMethyl redRed4.4 – 6.2YellowBromothymol blueYellow6.0 – 7.6BlueThymol blue (second transition)Yellow8.0 – 9.6BluePhenolphthaleinColourless8.3 – 10.0Fuchsia
Wide-range pH test papers with distinct colours for each pH from 1 to 14 are also available. Colour matching charts are supplied with the specific test strips purchased.
pls mark my answer as brainliest
Answered by
2
A universal indicator is a pH indicator composed of a solution of several compounds that exhibits several smooth colour changes over a pH value range from 0 to 14 (it may be negative or higher depending on the concentration) to indicate the acidity or alkalinity of solutions, where 7 indicates neutral.
example- Phenophlinepaper etc
example- Phenophlinepaper etc
Similar questions