Question:
Which of the following compound gives pink colour on reaction with phthalic anhydride in conc. \( \mathrm{H_2SO_4} \) followed by treatment with \( \mathrm{NaOH} \) ?
Which of the following compound gives pink colour on reaction with phthalic anhydride in conc. \( \mathrm{H_2SO_4} \) followed by treatment with \( \mathrm{NaOH} \) ?
Show Hint
This test is used to detect the presence of phenolic groups. Phenolphthalein is also one of the most common indicators used in acid-base titrations.
Updated On: Feb 2, 2026
- A
- B
- C
- D
Hide Solution
Verified By Collegedunia
The Correct Option is A
Solution and Explanation
Step 1: This is the Phthalein dye test.
Step 2: Phenol reacts with phthalic anhydride in the presence of $H_2SO_4$ to form Phenolphthalein.
Step 3: Phenolphthalein is a colorless indicator that turns deep pink/magenta in the presence of an alkali like $NaOH$.
Step 2: Phenol reacts with phthalic anhydride in the presence of $H_2SO_4$ to form Phenolphthalein.
Step 3: Phenolphthalein is a colorless indicator that turns deep pink/magenta in the presence of an alkali like $NaOH$.
Was this answer helpful?
0
0
Top Questions on Organic Chemistry
- An organic compound (A) on catalytic hydrogenation with \( \mathrm{H_2/Pt} \) gives tetralin, and on oxidation with hot alkaline \( \mathrm{KMnO_4} \) followed by acidification gives phthalic acid. Identify compound (A).
- JEE Main - 2026
- Chemistry
- Organic Chemistry
- \(\mathrm{C_6H_{12}O_3}\) gives positive iodoform test. On hydrolysis with dilute acid, the product formed gives both Tollens' test and iodoform test. Find the correct structure of \(\mathrm{C_6H_{12}O_3}\).
- JEE Main - 2026
- Chemistry
- Organic Chemistry
- The reactivity of the following compounds on the basis of the \( \mathrm{S_N1} \) mechanism is
- JEE Main - 2026
- Chemistry
- Organic Chemistry
- Which of the following is the correct order of nucleophilic nature for the following reaction? \[ \text{CH}_3\text{Br} + \text{Nu}^- \longrightarrow \text{CH}_3\text{Nu} + \text{Br}^- \]
- JEE Main - 2026
- Chemistry
- Organic Chemistry
- Which of the following is the correct order of reactivity of the given nucleophiles when treated with \( \text{CH}_3\text{Br} \) in methanol? \[ \text{F}^-,\ \text{I}^-,\ \text{C}_2\text{H}_5\text{O}^-,\ \text{C}_6\text{H}_5\text{O}^- \]
- JEE Main - 2026
- Chemistry
- Organic Chemistry
View More Questions
Questions Asked in JEE Main exam
- For two chemical reactions A and B, if the difference between their activation energy is 20 kJ at 300 K (R = 8.3 J K\(^{-1}\) mol\(^{-1}\)), determine \(\dfrac{k_2}{k_1}\).
- JEE Main - 2026
- Chemical Kinetics
- Consider a first order reaction: \[ A \rightarrow \text{products} \] 3 different solutions are taken and the rate of reaction of: Solution 1: 100 mL 10M \( A \) \( \rightarrow r_1 \) Solution 2: 200 mL 10M \( A \) \( \rightarrow r_2 \) Solution 3: 100 mL 10M \( A \) + 100 mL water \( \rightarrow r_3 \) The correct order of the rates of reactions is,
- JEE Main - 2026
- Chemical Kinetics
- Given at $10 \text{ AM}$, reaction is started (i) $A \xrightarrow{k} \text{Product}$ ($1^{\text{st}}$ order reaction) (ii) $BrO_3^- + 5Br^- \rightarrow 3Br_2$. At $10:10 \text{ AM}$, rate of disappearance of $Br^-$ was $2 \times 10^{-3} \text{ M/min}$ and concentration of $A$ was $0.1 \text{ M}$, if both reactions were proceed with same rate at this time then value of $k$ will be ?
- JEE Main - 2026
- Chemical Kinetics
- For given zero order reaction AB $\longrightarrow$ A$_2$ + B$_2$, the graph is given for decomposition of [AB]. Find half-life (t$_{1/2}$) in minutes?
- JEE Main - 2026
- Chemical Kinetics
Find temperature (in Kelvin) at which rate constant are equal for the following reaction?
\(\text{A $\rightarrow$ B, K = 10$^4$ e$^{-24000/T}$} \)
\(\text{P $\rightarrow$ Q, K = 10$^6$ e$^{-30000/T}$} \)- JEE Main - 2026
- Chemical Kinetics
View More Questions