The pH scale and indicators

9.What colour does red cabbage indicator turn in an acid?

10.Which of the following is a common alkali?

11.A solution has a pH of 2. Which indicator would be red in this solution?

12.What is the colour of phenolphthalein in a neutral solution?

13.A student adds a few drops of universal indicator to a solution and it turns green. What is the approximate pH of the solution?

14.A student tests four colourless liquids with red litmus paper. The results are: liquid X turns red litmus blue, liquid Y turns red litmus red, liquid Z turns red litmus blue, liquid W turns red litmus red. Which liquid is most likely to have a pH of 13?

15.A student adds universal indicator to three solutions: A (pH 4), B (pH 7), C (pH 10). Which row shows the correct colours?

16.A student has a solution of pH 2. They add phenolphthalein. What colour will the solution be?

17.Which of the following substances would turn blue litmus paper red?

18.A substance has a pH of 5. Which of the following is correct?

19.A student adds methyl orange to a solution and it turns yellow. Then they add an acid until the solution turns red. What is the pH range of the final solution?

20.A student measures the pH of a solution using an electronic pH meter and gets a reading of 8.5. Which indicator would be most suitable to confirm this pH?

21.A student has an unknown solution. When they add red cabbage indicator, it turns blue/green. What can they conclude?

22.A student tests four solutions with universal indicator. The results are: W: red, X: orange, Y: green, Z: purple. Which solution is most likely to be a strong acid?

23.A student adds universal indicator to a substance and it turns orange. What is the approximate pH?

24.A student uses an electronic pH meter to measure the pH of a solution and obtains a reading of 4.5. Which of the following indicators would be most suitable to visually confirm this pH?

25.A student adds a few drops of red cabbage indicator to a colourless solution. The indicator turns green. The student then adds an acid drop by drop until the colour changes to pink. What can be concluded about the original solution?

26.A student has four unlabelled solutions: W, X, Y, Z. Universal indicator gives the following colours: W - red, X - orange, Y - green, Z - purple. Which solution is most likely to be a strong alkali?

27.A student tests a solution with methyl orange and it turns yellow. They then add an acid until the solution turns red. What is the pH range of the final solution?

28.A student adds a few drops of universal indicator to a solution and it turns orange. What is the approximate pH of the solution?

29.A student adds universal indicator to a substance and it turns orange. The substance is then neutralised. What colour will the universal indicator turn?

30.Which of the following statements is true?

31.Which indicator remains colourless in an acid but turns pink in an alkali?

32.A student adds red cabbage indicator to a solution and it turns green. What is the pH of the solution?

33.Which of the following is a common acid?

34.A student tests a solution with methyl orange and it turns red. Which of the following could be the pH of the solution?

35.What colour does universal indicator turn in a strong acid?

36.A student adds a few drops of phenolphthalein to a solution and it remains colourless. Which of the following is a possible pH of the solution?

37.A student tests a solution with universal indicator and obtains a green colour. Which of the following could be the pH of the solution?

38.A student adds red cabbage indicator to a solution and it turns blue. What is the pH of the solution?

39.A student has four solutions: W, X, Y, Z. Universal indicator gives the following colours: W - red, X - orange, Y - green, Z - purple. Which solution is most likely to be a strong alkali?

40.A student adds a few drops of phenolphthalein to a colourless solution and it remains colourless. Then the student adds an alkali drop by drop. What colour change will be observed?

41.A substance with a pH of 4 is alkaline.

42.If blue litmus paper were placed in lemon juice, it would turn red.

43.If red litmus paper were placed in stomach acid, it would turn blue.

44.If phenolphthalein were placed in vinegar, it would turn pink.

45.Universal indicator would turn green when placed in pure water.

46.Methyl orange would turn red in milk.

47.Match each indicator to the colour it turns in an alkali.

48.Arrange the following pH values in order from most acidic to most alkaline: pH 2, pH 7, pH 9, pH 4.

49.Which of the following indicators change colour in an alkali? (Select all that apply.)

50.A student tests a solution with red cabbage indicator and it turns green. What is the approximate pH of the solution?

51.State two examples of common acids.

52.State two examples of common alkalis.

53.State the pH of a substance that is neutral and give an example of a neutral substance.

54.Describe an advantage of using an electronic pH meter over an indicator.

55.Universal indicator turns orange when placed into a substance. State what the pH of the substance might be.

56.Universal indicator turns orange when placed into a substance. The substance is now neutralised. What colour will the universal indicator turn?