" Universal Indicator "

In a experiment to measure the pH values of solutions, a student placed strips of universal indicator paper in foru beakes containig solutions A,B, C and D. The colour of universal indicator paper in these solutions is a shown below: The solution having lowes pH value is:

A student was given four unknown solutions in test tubes marked A,B,C and D and asked to test them with universal indicator solution. He observed that on putting universal indicator solution, the solutions A,B,C and D turned blue, orange, green and red respectively. The test tube which contains sodium chloride solution is:

(i) Define universal indicator. For what purpose it is used? (ii) Two solutions A and B have pH values of 3.0 and 9.5 respectively. Which of these will turn litmus solution from blue to red and which will turn phenolphthalein from colourless to pink? (iii) What is a neutral substance. WHat colour will you get when you add a few drops of universal you get when you add a few drops of universal indicator of a test tube containing distilled water?

In an experiment to measure the pH values by using a universal a universal indicator a student found that the pH values of four given solution A,B,C and D are 10,6,2 and 14 respectively. The solution which will require the maximum volume of sodium hydroxide solutioin for complete neutralisation is solution:

(a). What effect does the concentration of H^(+) (aq) ions have on the nature of a solution? (b). What effect does the concentration of OH^(-) ions have on the nature of a solution? (c). Someone put some universal indicator paper into vinegar. The pH is 3. What does this tell you about the vinegar? (d). Someone put some universal indicator paper onto wet soap. the pH is 8. What does this tell you about the soap? (e). State whether a solution is acidic, alkali or neutral if its pH is: (i) 9 (ii) 4 (iii) 7 (iv) 1 (v) 10 (vi) 3.

A student took a sodium salt and dissolved it in water. When this aqueous sodium salt solution was terted with universal indicator paper, its pH was found to be 9. (a) What does pH 9 tell us about the sodium salt solution. (b) Name one sodium salt which can produce such a solution.