All Exams Test series for 1 year @ ₹349 only
Question

Given below are four compounds :
(a) n-propyl choride
(b) iso-propyl chloride
(c) sec-butyl chloride
(d) neo-pentyl chloride
Percentage of carbon in the one which exhibits optical isomerism is :

The correct answer is
$56$

Identifying the Optically Active Compound

Optical isomerism occurs in compounds that possess a chiral center. A chiral center is typically a carbon atom bonded to four different functional groups.

  • n-propyl chloride (CH$_3$CH$_2$CH$_2$Cl): Contains no carbon atom bonded to four different groups.
  • iso-propyl chloride (CH$_3$CH(Cl)CH$_3$): The central carbon is bonded to H, Cl, and two identical CH$_3$ groups. Not chiral.
  • sec-butyl chloride (CH$_3$CH(Cl)CH$_2$CH$_3$): The second carbon atom (C2) is bonded to H, Cl, CH$_3$, and CH$_2$CH$_3$. These are four different groups, making it a chiral center. This compound exhibits optical isomerism.
  • neo-pentyl chloride ((CH$_3$)$_3$CCH$_2$Cl): Contains no carbon atom bonded to four different groups.

Therefore, sec-butyl chloride is the compound that exhibits optical isomerism.

Calculating Carbon Percentage in sec-butyl chloride

The molecular formula for sec-butyl chloride is C$_4$H$_9$Cl.

To find the percentage of carbon by mass, we use the atomic masses:

  • Atomic mass of Carbon (C) $\approx 12.011$ amu
  • Atomic mass of Hydrogen (H) $\approx 1.008$ amu
  • Atomic mass of Chlorine (Cl) $\approx 35.453$ amu

Calculate the molar mass of C$_4$H$_9$Cl:

Molar Mass $= (4 \times 12.011) + (9 \times 1.008) + (1 \times 35.453)$
Molar Mass $= 48.044 + 9.072 + 35.453 = 92.569$ amu

Calculate the percentage of carbon:

Percentage of Carbon $= \frac{\text{Mass of Carbon}}{\text{Molar Mass}} \times 100$
Percentage of Carbon $= \frac{4 \times 12.011}{92.569} \times 100$
Percentage of Carbon $= \frac{48.044}{92.569} \times 100 \approx 51.899\%$

Conclusion

sec-butyl chloride is the optically active compound. The calculated percentage of carbon is approximately $51.9\%$. Among the given options, $56$ is listed as the correct answer (Option A).

Was this answer helpful?

Similar Questions

  1. In Dumas method for estimation of nitrogen, 0.50 g of an organic compound gave 70 mL of nitrogen collected at 300 K and 715 mm pressure. The percentage of nitrogen in the organic compound is ______ %.
    (Aqueous tension at 300 K is 15 mm).
  2. Given below are two statements:
    Statement I: The dipole moment of R-CN is greater than R-NC and R-NC can undergo hydrolysis under acidic medium to produce
    Statement II: R-CN hydrolyses under acidic medium to produce a compound which on treatment with $\text{SOCl}_2$, followed by the addition of $\text{NH}_3$ gives another compound(x). This compound (x) on treatment with $\text{NaOCl/NaOH}$ gives a product, that on treatment with $\text{CHCl}_3\text{/KOH/}\Delta$ produces R-NC
    In the light of the above statements, choose the correct answer from the options given below

  3. Given below are two statements:
    Statement I: Cross aldol condensation between two different aldehydes will always produce four different products.
    Statement II: When semicarbazide reacts with a mixture of benzaldehyde and acetophenone under optimum pH, it forms a condensation product with acetophenone only.
    In the light of the above statements, choose the correct answer from the options given below
  4. $0.25 \text{ g}$ of an organic compound "A" containing carbon, hydrogen and oxygen was analysed using the combustion method. There was an increase in mass of $\text{CaCl}_2$ tube and potash tube at the end of the experiment. The amount was found to be $0.15 \text{ g}$ and $0.1837 \text{ g}$, respectively. The percentage of oxygen in compound A is ______ %. (Nearest integer)
    (Given: molar mass in $\text{g mol}^{-1}$ $\text{H} : 1, \text{C} : 12, \text{O} : 16$)
  5. Grignard reagent $\text{RMgBr (P)}$ reacts with water and forms a gas $\text{(Q)}$. One gram of Q occupies $1.4 \text{ dm}^3$ at STP. (P) on reaction with dry ice in dry ether followed by $\text{H}_3\text{O}^+$ forms a compound $\text{(Z)}$. 0.1 mole of $\text{(Z)}$ will weigh _________ g. (Nearest integer)
  6. The correct statements are :
    A. Activation energy for enzyme catalysed hydrolysis of sucrose is lower than that of acid catalysed hydrolysis.
    B. During denaturation, secondary and tertiary structures of a protein are destroyed but primary structure remains intact.
    C. Nucleotides are joined together by glycosidic linkage between $\text{C}_1$ and $\text{C}_4$ carbons of the pentose sugar.
    D. Quaternary structure of proteins represents overall folding of the polypeptide chain.
    Choose the correct answer from the options given below :
  7. By usual analysis, $1.00\text{ g}$ of compound (X) gave $1.79\text{ g}$ of magnesium pyrophosphate. The percentage of phosphorus in compound (X) is : __________ (nearest integer)
    (Given, molar mass in $\text{g\ mol}^{-1}$ : $\text{O} = 16, \text{Mg} = 24, \text{P} = 31$)
  8. The correct order of the rate of the reaction for the following reaction with respect to nucleophiles is :
    $\text{CH}_3\text{Br} + \text{Nu}^\ominus \longrightarrow \text{CH}_3\text{Nu} + \text{Br}^\ominus$
  9. Given below are two statements :
    Statement I : Compound (X), shown below, dissolves in $\text{NaHCO}_3$ solution and has two chiral carbon atoms
    Statement II : Compound (Y), shown below, has two carbons with $\text{sp}^3$ hybridization, one carbon with $\text{sp}^2$ and one carbon with $\text{sp}$ hybridization
    In the light of the above statements, choose the correct answer from the options given below :

  10. Consider the above sequence of reactions. The number of bromine atom(s) in the final product (P) will be :


Important Questions from Organic Chemistry

  1. In Dumas method for estimation of nitrogen, 0.50 g of an organic compound gave 70 mL of nitrogen collected at 300 K and 715 mm pressure. The percentage of nitrogen in the organic compound is ______ %.
    (Aqueous tension at 300 K is 15 mm).
  2. Given below are two statements:
    Statement I: The dipole moment of R-CN is greater than R-NC and R-NC can undergo hydrolysis under acidic medium to produce
    Statement II: R-CN hydrolyses under acidic medium to produce a compound which on treatment with $\text{SOCl}_2$, followed by the addition of $\text{NH}_3$ gives another compound(x). This compound (x) on treatment with $\text{NaOCl/NaOH}$ gives a product, that on treatment with $\text{CHCl}_3\text{/KOH/}\Delta$ produces R-NC
    In the light of the above statements, choose the correct answer from the options given below

  3. Given below are two statements:
    Statement I: Cross aldol condensation between two different aldehydes will always produce four different products.
    Statement II: When semicarbazide reacts with a mixture of benzaldehyde and acetophenone under optimum pH, it forms a condensation product with acetophenone only.
    In the light of the above statements, choose the correct answer from the options given below
  4. $0.25 \text{ g}$ of an organic compound "A" containing carbon, hydrogen and oxygen was analysed using the combustion method. There was an increase in mass of $\text{CaCl}_2$ tube and potash tube at the end of the experiment. The amount was found to be $0.15 \text{ g}$ and $0.1837 \text{ g}$, respectively. The percentage of oxygen in compound A is ______ %. (Nearest integer)
    (Given: molar mass in $\text{g mol}^{-1}$ $\text{H} : 1, \text{C} : 12, \text{O} : 16$)
  5. Grignard reagent $\text{RMgBr (P)}$ reacts with water and forms a gas $\text{(Q)}$. One gram of Q occupies $1.4 \text{ dm}^3$ at STP. (P) on reaction with dry ice in dry ether followed by $\text{H}_3\text{O}^+$ forms a compound $\text{(Z)}$. 0.1 mole of $\text{(Z)}$ will weigh _________ g. (Nearest integer)
Need Expert Advice?
More Questions from JEE Main

Start Your Preparation with Prepp Mobile App

Download the app from Google Play & App Store
Download the app from Google Play & App Store
Prepp Mobile App