What is the colour of phenolphthalein in soap solution?a)Pinkb)orangec)colorlessd)blueCorrect answer is option 'A'. Can you explain this answer?

Question

Answer

Phenolphthalein shows pink colour in basic solution and soap solution is basic that is why it shows pink colour in soap solution.

Answer

Phenolphthalein is an indicator it show pink colour in soap because  the soap is basic in nature .

Answer

Phenolphthalein is a commonly used chemical indicator that is often used in chemistry experiments to determine the pH of a solution. It is a colorless compound in its acidic form and turns pink in the presence of a base.

When phenolphthalein is added to a soap solution, it turns pink. This indicates that the soap solution is basic in nature. Soap is typically made by the saponification of fats or oils with a strong base, such as sodium hydroxide (NaOH) or potassium hydroxide (KOH). This process produces soap molecules and glycerol.

The soap molecules have a polar head and a nonpolar tail. The polar head is attracted to water molecules, while the nonpolar tail is repelled by water. This property allows soap to dissolve in water and form micelles, which are spherical structures where the nonpolar tails are shielded from the water molecules, while the polar heads remain in contact with water.

When phenolphthalein is added to a soap solution, it interacts with the hydroxide ions (OH-) present in the solution. Phenolphthalein is a weak acid and its pink color is due to the presence of hydroxide ions. The hydroxide ions react with the phenolphthalein, causing it to change color from colorless to pink.

The pink color indicates that the soap solution is basic, as the hydroxide ions are indicative of a basic solution. This is because the soap solution contains excess hydroxide ions from the saponification process. The hydroxide ions help in breaking down oils and greases, making the soap solution effective in removing dirt and stains.

In summary, phenolphthalein turns pink in a soap solution because the soap solution is basic in nature. The presence of excess hydroxide ions from the saponification process causes the phenolphthalein to change color.

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