Aldehydes, Ketones and Carboxylic Acids
Identify the structure of the final product (D) in the following sequence of the reactions :
Total number of $\mathrm{sp}^2$ hybridised carbon atoms in product D is ____________.
Explanation:
$\Rightarrow$ Number of $\mathrm{sp}^2 \mathrm{C}$-atoms in product $\mathrm{D}=7$
Explanation:
Mass of benzaldehyde = 5.3 g
Mass of product = 3.51 g
Claisen - Schmidt reaction :
Condensation of aromatic aldehydes / ketones (without alpha-hydrogen) with diphatic aldehydes /ketones (with alpha-hydrogen) in the presence of weak base to form $\alpha,\beta$-unsaturated aldehydes/ketones.
Given
benzaldehyde $\to$ dibenzalacetone
Formula of percent yield
Percent yield $ = {{actual\,yield} \over {Theoretical\,yield}} \times 100$
Actual yield = 3.51 g
From the reaction, the stoichiometric ratio between benzaldehyde and dibenzal acetone is 2 : 1
benzaldehyde : dibenzalacetone
$2:1$
$1:{1 \over 2}$
Moles of benzaldehyde:
$Moles = {{Mass} \over {Molar\,mass}}$
$ = {{5.3\,g} \over {106.12\,g/mol}}$
= 0.04994 mol
Molarmass of benzaldehyde = 106.12 g/mol
For 1 mole of benzaldehyde, $\frac{1}{2}$ moles product (dibenzalacetone) is formed.
So, for 0.04994 mol benzaldehyde, $\frac{1}{2}\times0.04994$ mol dibenzalacetone is formed.
So, moles of dibenzalacetone = 0.02497 mol
Mass of product dibenzalacetone (Theoretical yield)
Mass = moles $\times$ molarmass
$=0.02497$ mol $\times$ $234.29$ g/mol
= 5.850 g
Percent yield $ = {{3.51\,g} \over {5.85\,g}} \times 100$
$ = 0.6 \times 100 = 60\% $
A compound ' $\mathrm{X}^{\prime}$ absorbs 2 moles of hydrogen and ' X ' upon oxidation with $\mathrm{KMnO}_4 \mid \mathrm{H}^{+}$ gives
The total number of $\sigma$ bonds present in the compound ' $X^{\prime}$ ' is __________.
Explanation:
A molecule ("P") on treatment with acid undergoes rearrangement and gives ("Q"). ("Q") on ozonolysis followed by reflux under alkaline condition gives (" $R$ "). The structure of (" $R$ ") is given below.
The structure of ("P") is
Monocyclic compounds $\mathbf{P}, \mathbf{Q}, \mathbf{R}$ and $\mathbf{S}$ are the major products formed in the reaction sequences given below.
The product having the highest number of unsaturated carbon atom(s) is :
P
Q
R
S
In the above reaction product 'P' is
Which of the following compounds will give silver mirror with ammoniacal silver nitrate?
A. Formic acid
B. Formaldehyde
C. Benzaldehyde
D. Acetone
Choose the correct answer from the options given below :
Identify major product "X" formed in the following reaction :
What is the structure of C?
Identify the product (P) in the following reaction:
Consider the given reaction, identify the major product P.
Which among the following aldehydes is most reactive towards nucleophilic addition reactions?
Identify A and B in the given chemical reaction sequence :
Consider the given chemical reaction :
Product "A" is :
Identify 'A' in the following reaction :
Given below are two statements :
Statements I : Acidity of $\alpha$-hydrogens of aldehydes and ketones is responsible for Aldol reaction.
Statement II : Reaction between benzaldehyde and ethanal will NOT give Cross - Aldol product.
In the light of the above statements, choose the most appropriate answer from the options given below :
Identify the product in the following reaction:
| List I (Reactions) | List II (Reagents) |
|---|---|
(A)  |
(I) CH3MgBr, H2O |
| (B) C6H5COC6H5 ⟶ C6H5CH=C6H5 | (II) Zn(Hg) and conc. HCl |
| (C) C6H5CHO ⟶ C6H5CH(OH)CH3 | (III) NaBH4, H+ |
(D)  |
(IV) DIBAL-H, H2O |
Choose the correct answer from the options given below :
Identify major product 'P' formed in the following reaction.
Identify the name reaction.
Salicylaldehyde is synthesized from phenol, when reacted with
m-chlorobenzaldehyde on treatment with 50% KOH solution yields :
This reduction reaction is known as:
Structure of 4-Methylpent-2-enal is :
Identify the reagents used for the following conversion
The molecular formula of second homologue in the homologous series of mono carboxylic acids is
Highest enol content will be shown by:
Two moles of benzaldehyde and one mole of acetone under alkaline conditions using aqueous $\mathrm{NaOH}$ after heating gives $x$ as the major product. The number of $\pi$ bonds in the product $x$ is ______.
Explanation:
Total number of $\pi$ bonds in $X=9$
The product C in the following sequence of reactions has ________ $\pi$ bonds.
Explanation:
Number of $\pi$ bonds in (C) = 4
In the Claisen-Schmidt reaction to prepare $351 \mathrm{~g}$ of dibenzalacetone using $87 \mathrm{~g}$ of acetone, the amount of benzaldehyde required is _________ g. (Nearest integer)
Explanation:
$\begin{aligned} & \text { mol of benzaldehyde required }=1.5 \times 2 \\ &=3 \mathrm{~mol} \\ & \text { mass }=318 \mathrm{~g} \end{aligned}$
Vanillin compound obtained from vanilla beans, has total sum of oxygen atoms and $\pi$ electrons is __________.
Explanation:
To determine the total sum of oxygen atoms and $\pi$ electrons in vanillin, let's first consider the structure of vanillin. Vanillin is an organic compound with the chemical formula $C_8H_8O_3$. It consists of a benzene ring attached to a methoxy group (-OCH3), a hydroxyl group (-OH), and an aldehyde group (-CHO).
Firstly, let's count the oxygen atoms:
- One from the methoxy group (-OCH3)
- One from the hydroxyl group (-OH)
- One from the aldehyde group (-CHO)
Thus, there are a total of 3 oxygen atoms in vanillin.
Next, let's calculate the total number of $\pi$ electrons:
- The benzene ring has 3 double bonds, contributing 6 $\pi$ electrons.
- The aldehyde group has 1 double bond (C=O), contributing 2 $\pi$ electrons.
- The methoxy group and the hydroxyl group do not contribute any $\pi$ electrons since they do not have $\pi$ bonds in their structures.
Therefore, vanillin has a total of 8 $\pi$ electrons from the benzene ring and the aldehyde group.
Adding the number of oxygen atoms (3) and the $\pi$ electrons (8) gives us a total sum of 11.
Thus, the total sum of oxygen atoms and $\pi$ electrons in vanillin is 11.
The product of the following reaction is P.
The number of hydroxyl groups present in the product P is ________.
Explanation:
Product benzene has zero hydroxyl group
The total number of 'Sigma' and 'Pi' bonds in 2-formylhex-4-enoic acid is _________.
Explanation:
Sigma bonds : 19
pi bonds : 3
From the compounds given below, number of compounds which give positive Fehling's test is _________.
Benzaldehyde, Acetaldehyde, Acetone, Acetophenone, Methanal, 4nitrobenzaldehyde, cyclohexane carbaldehyde.
Explanation:
Acetaldehyde $(\mathrm{CH}_3 \mathrm{CHO})$, Methanal $(\mathrm{HCHO})$, and cyclohexane carbaldehyde 
In the following reaction sequence, the major product $\mathbf{Q}$ is
List-I contains various reaction sequences and List-II contains the possible products. Match each entry in List-I with the appropriate entry in List-II and choose the correct option.
| List-I | List-II |
|---|---|
|
|
|
|
|
|
|
|
|
An organic compound $\mathbf{P}$ having molecular formula $\mathrm{C}_6 \mathrm{H}_6 \mathrm{O}_3$ gives ferric chloride test and does not have intramolecular hydrogen bond. The compound $\mathbf{P}$ reacts with 3 equivalents of $\mathrm{NH}_2 \mathrm{OH}$ to produce oxime $\mathbf{Q}$. Treatment of $\mathbf{P}$ with excess methyl iodide in the presence of $\mathrm{KOH}$ produces compound $\mathbf{R}$ as the major product. Reaction of $\mathbf{R}$ with excess iso-butylmagnesium bromide followed by treatment with $\mathrm{H}_3 \mathrm{O}^{+}$gives compound $\mathbf{S}$ as the major product.
The total number of methyl $\left(-\mathrm{CH}_3\right)$ group(s) in compound $\mathbf{S}$ is ___.
Explanation:
$\therefore$ Sum of oxygen atoms in $\mathrm{S}$ and $\mathrm{T}=1+1=2$
Explanation:
$\begin{aligned} & \text { Molecular mass of polymers }=(104 \times 500)+(118 \times 500)-18 \times 999 \\\\ & =52000+59000-17982=93018\end{aligned}$
Complete reaction of acetaldehyde with excess formaldehyde, upon heating with conc. $\mathrm{NaOH}$ solution, gives $\mathbf{P}$ and $\mathbf{Q}$. Compound $\mathbf{P}$ does not give Tollens' test, whereas $\mathbf{Q}$ on acidification gives positive Tollens' test. Treatment of $\mathbf{P}$ with excess cyclohexanone in the presence of catalytic amount of $p$-toluenesulfonic acid (PTSA) gives product $\mathbf{R}$.
Sum of the number of methylene groups $\left(-\mathrm{CH}_2-\right)$ and oxygen atoms in $\mathbf{R}$ is __________.
Explanation:
Number of $\mathrm{CH}_2$ groups in $\mathrm{R}=14$
Number of $\mathrm{O}$-atoms $=4$
Required Answer $=14+4=18$
In the above conversion the correct sequence of reagents to be added is
In the reaction given below
'A' is
The two products formed in above reaction are -
'A' in the above reaction is:
In the following reaction
'A' is
The major product 'P' formed in the following sequence of reactions is
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R.
Assertion A : A solution of the product obtained by heating a mole of glycine with a mole of chlorine in presence of red phosphorous generates chiral carbon atom.
Reason R : A molecule with 2 chiral carbons is always optically active.
In the light of the above statements, choose the correct answer from the options given below:
'A' and 'B' in the above reactions are:
