Find the best tutors and institutes for Class 11 Tuition
Q9.8(iii):
Write chemical equations for combustion reaction of the following hydrocarbons: (iii) Hexyne
Solution :
Step 1: Determining the Molecular Formula
Hexyne is an alkyne with the general formula $C_nH_{2n-2}$. For "hex" (where $n=6$):
$C_6H_{2(6)-2} = C_6H_{10}$
[Per IUPAC nomenclature and homologous series rules for alkynes].
Step 2: Defining the Combustion Reaction
Complete combustion of a hydrocarbon requires oxygen ($O_2$) to produce carbon dioxide ($CO_2$) and water ($H_2O$). The unbalanced chemical equation is:
$C_6H_{10} + O_2 \rightarrow CO_2 + H_2O$
Step 3: Balancing the Chemical Equation
To balance the equation, we follow the principle of Conservation of Mass [Per the Law of Conservation of Mass]:
- Carbon (C): 6 atoms on the left require $6CO_2$ on the right.
- Hydrogen (H): 10 atoms on the left require $5H_2O$ on the right (since $5 \times 2 = 10$).
- Oxygen (O): On the right, we have $(6 \times 2) + (5 \times 1) = 17$ oxygen atoms. To obtain 17 atoms from $O_2$, we require $\frac{17}{2}$ molecules of $O_2$.
The balanced equation is:
$C_6H_{10} + \frac{17}{2}O_2 \rightarrow 6CO_2 + 5H_2O$
Step 4: Converting to Integer Coefficients
To eliminate the fraction, multiply the entire equation by 2:
$2C_6H_{10} + 17O_2 \rightarrow 12CO_2 + 10H_2O$
Visual Representation of Stoichiometry
Data Summary Table
| Species | Coefficient | Atomic Contribution |
|---|---|---|
| $C_6H_{10}$ | 2 | 12 C, 20 H |
| $O_2$ | 17 | 34 O |
| $CO_2$ | 12 | 12 C, 24 O |
| $H_2O$ | 10 | 20 H, 10 O |
Final Solution: The balanced combustion reaction for hexyne is 2C_6H_{10} + 17O_2 \rightarrow 12CO_2 + 10H_2O
More Questions from Class 11 Chemistry Hydrocarbons EXERCISES
- Q9.1: How do you account for the formation of ethane during chlorination of methane ?
- Q9.10: Why is benzene extra ordinarily stable though it contains three double bonds?
- Q9.11: What are the necessary conditions for any system to be aromatic?
- Q9.12(i): Explain why the following systems are not aromatic? (i)
- Q9.12(ii): Explain why the following systems are not aromatic? (ii)
- Q9.12(iii): Explain why the following systems are not aromatic? (iii)
- Q9.13(i): How will you convert benzene into (i) p-nitrobromobenzene
- Q9.13(ii): How will you convert benzene into (ii) m- nitrochlorobenzene
- Q9.13(iii): How will you convert benzene into (iii) p - nitrotoluene
- Q9.13(iv): How will you convert benzene into (iv) acetophenone?
- Q9.14: In the alkane $H_3C – CH_2 – C(CH_3)_2 – CH_2 – CH(CH_3)_2$, identify $1^\circ,2^\circ,3^\circ$ carbon atoms and give the number of $H$ atoms bonded to each one of these.
- Q9.15: What effect does branching of an alkane chain has on its boiling point?
- Q9.16: Addition of HBr to propene yields 2-bromopropane, while in the presence of benzoyl peroxide, the same reaction yields 1-bromopropane. Explain and give mechanism.
- Q9.17: Write down the products of ozonolysis of 1,2-dimethylbenzene (o-xylene). How does the result support Kekulé structure for benzene?
- Q9.18: Arrange benzene, n-hexane and ethyne in decreasing order of acidic behaviour. Also give reason for this behaviour.
- Q9.19: Why does benzene undergo electrophilic substitution reactions easily and nucleophilic substitutions with difficulty?
- Q9.2(a): Write IUPAC names of the following compounds : (a) $CH_3CH=C(CH_3)_2$
- Q9.2(b): Write IUPAC names of the following compounds : (b) $CH_2=CH-C \equiv C-CH_3$
- Q9.2(c): Write IUPAC names of the following compounds : (c)
- Q9.2(d): Write IUPAC names of the following compounds : (d)
- Q9.2(e): Write IUPAC names of the following compounds : (e)
- Q9.2(f): Write IUPAC names of the following compounds : (f) $CH_3(CH_2)_4 CH (CH_2)_3 CH_3$ with a $CH_2–CH(CH_3)_2$ group attached to the CH.
- Q9.2(g): Write IUPAC names of the following compounds : (g) $CH_3 – CH = CH – CH_2 – CH = CH – CH – CH_2 – CH = CH_2$ with a $C_2H_5$ group attached to the third CH from the left.
- Q9.20(i): How would you convert the following compounds into benzene? (i) Ethyne
- Q9.20(ii): How would you convert the following compounds into benzene? (ii) Ethene
- Q9.20(iii): How would you convert the following compounds into benzene? (iii) Hexane
- Q9.21: Write structures of all the alkenes which on hydrogenation give 2-methylbutane.
- Q9.22(a): Arrange the following set of compounds in order of their decreasing relative reactivity with an electrophile, $E^+$ (a) Chlorobenzene, 2,4-dinitrochlorobenzene, p-nitrochlorobenzene
- Q9.22(b): Arrange the following set of compounds in order of their decreasing relative reactivity with an electrophile, $E^+$ (b) Toluene, $p-H_3C – C_6H_4 – NO_2$, $p-O_2N – C_6H_4 – NO_2$.
- Q9.23: Out of benzene, m–dinitrobenzene and toluene which will undergo nitration most easily and why?
- Q9.24: Suggest the name of a Lewis acid other than anhydrous aluminium chloride which can be used during ethylation of benzene.
- Q9.25: Why is Wurtz reaction not preferred for the preparation of alkanes containing odd number of carbon atoms? Illustrate your answer by taking one example.
- Q9.3(a): For the following compounds, write structural formulas and IUPAC names for all possible isomers having the number of double or triple bond as indicated : (a) $C_4H_8$ (one double bond)
- Q9.3(b): For the following compounds, write structural formulas and IUPAC names for all possible isomers having the number of double or triple bond as indicated : (b) $C_5H_8$ (one triple bond)
- Q9.4(i): Write IUPAC names of the products obtained by the ozonolysis of the following compounds : (i) Pent-2-ene
- Q9.4(ii): Write IUPAC names of the products obtained by the ozonolysis of the following compounds : (ii) 3,4-Dimethylhept-3-ene
- Q9.4(iii): Write IUPAC names of the products obtained by the ozonolysis of the following compounds : (iii) 2-Ethylbut-1-ene
- Q9.4(iv): Write IUPAC names of the products obtained by the ozonolysis of the following compounds : (iv) 1-Phenylbut-1-ene
- Q9.5: An alkene ‘A’ on ozonolysis gives a mixture of ethanal and pentan-3-one. Write structure and IUPAC name of ‘A’.
- Q9.6: An alkene ‘$A$’ contains three $C – C$, eight $C – H$ $\sigma$ bonds and one $C – C$ $\pi$ bond. ‘$A$’ on ozonolysis gives two moles of an aldehyde of molar mass 44 u. Write IUPAC name of ‘$A$’.
- Q9.7: Propanal and pentan-3-one are the ozonolysis products of an alkene? What is the structural formula of the alkene?
- Q9.8(i): Write chemical equations for combustion reaction of the following hydrocarbons: (i) Butane
- Q9.8(ii): Write chemical equations for combustion reaction of the following hydrocarbons: (ii) Pentene
- Q9.8(iv): Write chemical equations for combustion reaction of the following hydrocarbons: (iv) Toluene
- Q9.9: Draw the cis and trans structures of hex-2-ene. Which isomer will have higher b.p. and why?
CBSE Solutions for Class 11 Chemistry Hydrocarbons
Chapters in CBSE - Class 11 Chemistry
Top Tutors who teach Hydrocarbons
Top Tutor
Narasapur, Gadag
10 yrs of
Exp
1 student
60 hrs of classes completed
350
per hour
Online Classes
I specialize in breaking down complex mathematical derivations, interpreting complex velocity-time or field graphs, and explaining the physical significance behind equations.Step-by-step algorithmic breakdown of complex integrals, visualizing 3D space geometries, and teaching the underlying logic of proofs.I break down intimidating, high-weightage topics into digestible sub-concepts. For example, before diving into complex Electromagnetic Induction problems, I ensure the student thoroughly grips Lenz's Law and magnetic flux concepts.
Top Tutor
Malviya Nagar, Delhi
15 yrs of
Exp
7 students
3 hrs of classes completed
400
per hour
Student's Home
I have 15 years experience in home tuition
Top Tutor
Mathara, Kozhikode
12 yrs of
Exp
3 students
919 hrs of classes completed
700
per hour
Online Classes
I can explain the concepts with clarity. I focus on solving numerical problems in Physics so that a student can learn better.
Top Tutor
New Town, Kolkata
10 yrs of
Exp
19 students
20 hrs of classes completed
130
per hour
Online Classes
Tutor's home
I am a strong believer in concept-based gain of knowledge. I start from scratch while teaching the very basic concepts and take my students to a level where they have a deep understanding of the subject. Once they understand the concept, the next step is that practice a lot of questions/numerical/problem in the class itself as practice is the key to retain knowledge. I refer to prescribed books by CBSE/ICSE board considering school exams but always encourage students to refer additional 1 or 2 books (like H C Verma/ B M Sharma/ D C Pandey) for JEE/NEET based on their speed to practice. In last I provide them enough homework to practice at home and send me the doubts before the next class.
Amazing talented and easy teaching methods. Can't continue because of timing issues. But definitely will definitely join again.
Super Tutor
Nerul, Mumbai
10 yrs of
Exp
6 students
700 hrs of classes completed
800
per hour
Online Classes
I'm an ex-faculty member of Allen, FIITJEE & Unacademy, and I taught in DAV for 2 years. Now I'm working as a freelancer. I have more than 10 years of experience. So overall I've all kinds of experience to meet with academic & JEE aspirants as well. Join me to learn mathematics from basic to advanced.
Sir, explains topics very clearly nicely explains doubt very nicely with high conceptual knowledge.
