When ethanal is treated with Fehling's solution, it gives a precipitate of
- $ Cu_{2}O $
- $Cu$
- $ Cu_{3}O $
- $ CuO $
The Correct Option is A
Solution and Explanation
$\underset{\text{ethanal}}{CH_3CHO} + \underset{\text{(from Fehling solution)}}{2CuO} \rightarrow CH_3COOH + \underset{\text{red ppt.}}{Cu_2O \downarrow}$
Top Questions on Aldehydes, Ketones and Carboxylic Acids
- What do you understand by these following terms? Give one example of each.
(i) Aldol (ii) Schiff's base (iii) Cannizaro's reaction (iv) Oxime (v) Acetal- UP Board XII - 2025
- Chemistry
- Aldehydes, Ketones and Carboxylic Acids
In the given reaction sequence, the structure of Y would be:
- CBSE CLASS XII - 2025
- Chemistry
- Aldehydes, Ketones and Carboxylic Acids
- Identify the sets containing correct order against the property mentioned from the following
- TS EAMCET - 2025
- Chemistry
- Aldehydes, Ketones and Carboxylic Acids
- What are X, Y, Z respectively in the following reaction sequence?
CH$_3$CH=CHCH$_3$ $\xrightarrow{X}$ CH$_3$COOH $\xrightarrow{Y}$ CH$_3$CO-Cl $\xrightarrow{Z, C6H5NH2}$ C$_6$H$_5$NHCOCH$_3$- TS EAMCET - 2025
- Chemistry
- Aldehydes, Ketones and Carboxylic Acids
- An amine X (C4H11N) on heating with CHCl3 in ethanolic KOH forms a foul-smelling substance. Product of other amine Y (C4H11N) and benzenesulphonyl chloride is insoluble in alkali. What are X and Y respectively?
- TS EAMCET - 2025
- Chemistry
- Aldehydes, Ketones and Carboxylic Acids
Questions Asked in JEE Advanced exam
The center of a disk of radius $ r $ and mass $ m $ is attached to a spring of spring constant $ k $, inside a ring of radius $ R>r $ as shown in the figure. The other end of the spring is attached on the periphery of the ring. Both the ring and the disk are in the same vertical plane. The disk can only roll along the inside periphery of the ring, without slipping. The spring can only be stretched or compressed along the periphery of the ring, following Hooke’s law. In equilibrium, the disk is at the bottom of the ring. Assuming small displacement of the disc, the time period of oscillation of center of mass of the disk is written as $ T = \frac{2\pi}{\omega} $. The correct expression for $ \omega $ is ( $ g $ is the acceleration due to gravity):
- JEE Advanced - 2025
- Waves and Oscillations
- Consider the vectors $$ \vec{x} = \hat{i} + 2\hat{j} + 3\hat{k},\quad \vec{y} = 2\hat{i} + 3\hat{j} + \hat{k},\quad \vec{z} = 3\hat{i} + \hat{j} + 2\hat{k}. $$ For two distinct positive real numbers $ \alpha $ and $ \beta $, define $$ \vec{X} = \alpha \vec{x} + \beta \vec{y} - \vec{z},\quad \vec{Y} = \alpha \vec{y} + \beta \vec{z} - \vec{x},\quad \vec{Z} = \alpha \vec{z} + \beta \vec{x} - \vec{y}. $$ If the vectors $ \vec{X}, \vec{Y}, \vec{Z} $ lie in a plane, then the value of $ \alpha + \beta - 3 $ is ________.
- If $$ \alpha = \int_{\frac{1}{2}}^{2} \frac{\tan^{-1} x}{2x^2 - 3x + 2} \, dx, $$ then the value of $ \sqrt{7} \tan \left( \frac{2\alpha \sqrt{7}}{\pi} \right) $ is.
(Here, the inverse trigonometric function $ \tan^{-1} x $ assumes values in $ \left( -\frac{\pi}{2}, \frac{\pi}{2} \right) $.)- JEE Advanced - 2025
- Integral Calculus
Let $ a_0, a_1, ..., a_{23} $ be real numbers such that $$ \left(1 + \frac{2}{5}x \right)^{23} = \sum_{i=0}^{23} a_i x^i $$ for every real number $ x $. Let $ a_r $ be the largest among the numbers $ a_j $ for $ 0 \leq j \leq 23 $. Then the value of $ r $ is ________.
- JEE Advanced - 2025
- binomial expansion formula
- The total number of real solutions of the equation $$ \theta = \tan^{-1}(2 \tan \theta) - \frac{1}{2} \sin^{-1} \left( \frac{6 \tan \theta}{9 + \tan^2 \theta} \right) $$ is
(Here, the inverse trigonometric functions $ \sin^{-1} x $ and $ \tan^{-1} x $ assume values in $[-\frac{\pi}{2}, \frac{\pi}{2}]$ and $(-\frac{\pi}{2}, \frac{\pi}{2})$, respectively.)- JEE Advanced - 2025
- Inverse Trigonometric Functions
Concepts Used:
Aldehydes, Ketones, and Carboxylic Acids
Aldehydes, Ketones, and Carboxylic Acids are carbonyl compounds that contain a carbon-oxygen double bond. These organic compounds are very important in the field of organic chemistry and also have many industrial applications.
Aldehydes:
Aldehydes are organic compounds that have the functional group -CHO.
Preparation of Aldehydes
Acid chlorides are reduced to aldehydes with hydrogen in the presence of palladium catalyst spread on barium sulfate.
Ketones:
Ketones are organic compounds that have the functional group C=O and the structure R-(C=O)-R’.
Preparation of Ketones
Acid chlorides on reaction with dialkyl cadmium produce ketones. Dialkyl cadmium themselves are prepared from Grignard reagents.
Carboxylic Acid:
Carboxylic acids are organic compounds that contain a (C=O)OH group attached to an R group (where R refers to the remaining part of the molecule).
Preparation of Carboxylic Acids
Primary alcohols are readily oxidized to carboxylic acids with common oxidizing agents such as potassium permanganate in neutral acidic or alkaline media or by potassium dichromate and chromium trioxide in acidic media.