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Suppose you have four test tubes labelled as 'A', 'B', 'C' and 'D', 'A' contains plain water, 'B' contains the solution of alkali, 'C' contains the solution of an acid, and 'D' contains the solution of sodium chloride. Which one of these solutions will turn phenolphthalein solution pink?

Suppose you have four test tubes labelled as 'A', 'B', 'C' and 'D', 'A' contains plain water, 'B' contains the solution of alkali, 'C' contains the solution of an acid, and 'D' contains the solution of sodium chloride. Which one of these solutions will turn phenolphthalein solution pink? Correct Answer Solution ‘B’

The correct answer is option 2 i.e. Solution 'B'

Phenolphthalein as a pH indicator.

  • Phenolphthalein is a chemical compound with the formula C20H14O4 and is often denoted as "HIn" or "phph".
  • Phenolphthalein is often used as an indicator in acid-base titrations.
  • It turns colourless in acidic solutions and pink in basic or alkali solutions. Hence option 2 is correct.
  • It is dissolved with alcohol and it is slightly soluble in water.
  • It does not have taste and smell. 
  •  It is a weak acid, which can lose H+ ions in solution.

Related Questions

Suppose you have four test tubes labelled as 'A', 'B', 'C' and 'D'. 'A' contains plain water, 'B' contains solution of an alkali, 'C' contains solution of an acid, and 'D' contains solution of sodium chloride. Which one of these solution will turn phenophthalein solution pink?
There are three test tubes A, B and C, all having colorless liquid of equal volume and strength. A drop of Phenolphthalein is added to each of them. It is observed that test tubes A and B remain colorless while C becomes pink. When the pink solution of C is added to A and B, it is observed that A remains colorless but B attains pink color. Which of the following is correct inference?
You have two test tubes 'A' and 'B'. Test tube 'A' contains paste of turmeric whereas test tube 'B' contains aqueous solution of phenolphthalein. On adding a few drops of dilute hydrochloric acid to these test tubes the contents of:
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Which one is incorrect match:-   TITRATION INDICATOR 1) Strong acid v/s strong base Phenolphthalein & methyl Orange 2) Weak acid v/s strong base Phenolphthalein 3) Strong acid v/s weak base Methyl orange 4) Weak acid v/s weak base Methyl Red
Five containers of different shapes sphere, cube, prism, cuboid and cylinder have different patterns plain, checkered, floral, polka dots and stripes but not necessarily in the same order. Also each has a different colour blue, green, pink, black and yellow but not necessarily in the same order. The cube and cylinder don't have floral design. Sphere is pink in colour. Prism has checkered design but is not yellow or black in colour. Cuboid is green in colour but doesn't have polka dots or stripes pattern. The plain container is pink in colour. Cube has polka dots and neither blue nor black in colour. Cylinder is not blue in colour. Which container has floral pattern?
In a survey of 100 students, it was found that 25 students have enrolled for Navy AA test series, 26 students have enrolled for NDA test series, 26 students have enrolled for Airforce group X test series, 9 students have enrolled for both Navy AA and Airforce group X test series, 11 students have enrolled for both Navy AA and NDA test series, 8 students have enrolled for both NDA and Airforce group X test series whereas 3 students have enrolled in all three test series. Find the number of students who have enrolled in exactly one test series.
In a survey of 100 students, it was found that 25 students have enrolled for Navy AA test series, 26 students have enrolled for NDA test series, 26 students have enrolled for Airforce group X test series, 9 students have enrolled for both Navy AA and Airforce group X test series, 11 students have enrolled for both Navy AA and NDA test series, 8 students have enrolled for both NDA and Airforce group X test series whereas 3 students have enrolled in all three test series. Find the number of students who have enrolled exactly in any two test series.
In a batch process, the reaction takes place in the presence of an acid medium. The acid is drained from the reaction vessel at the rate of 15ml/s as a result of the density difference of the acid from the reacting component. To avoid wastage of acid, it is recycled to an acid tank which has 1000 L capacity. The acid drained from the reaction vessel, picks up 50 g/L solids from the reactor. Acid is fed once again to the process from acid tank. When the process is started, the acid is almost pure in the tank as a result of filtration. As the reaction proceeds, acid in the tank gets more and more contaminated with the solids. The concentration of the solids should not exceed 100 g/L from the process point of view. The batch time is 16h. Estimate whether the concentration of the solids will exceed 100g/L during the batch reaction.