Hydrocarbons - Class 11 Chemistry - Chapter 9 - Notes, NCERT Solutions & Extra Questions
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Extra Questions - Hydrocarbons | NCERT | Chemistry | Class 11
The major products obtained when a mixture of cyclohexane and cyclopentane is heated to 300 degrees Celsius in the presence of platinum are:
When a mixture of cyclohexane and cyclopentane is heated to $300^\circ\mathrm{C}$ in the presence of platinum (Pt), a notable transformation occurs for cyclohexane but not for cyclopentane. Under these conditions, cyclohexane undergoes a dehydrogenation reaction catalyzed by platinum, transforming into benzene due to its aromaticity and greater stability.
On the other hand, cyclopentane remains unaltered under these conditions. Although it could theoretically also undergo a transformation to form cyclopentadiene, this compound is non-aromatic and less stable compared to cyclopentane. Therefore, cyclopentane does not convert into cyclopentadiene.
Hence, the major products formed in this reaction are:
Benzene
Cyclopentane
Ozone depletion is caused by chlorofluorocarbons.
A) True
B) False
Solution
The correct answer is A) True.
Chlorofluorocarbons (CFCs), formerly used in aerosol spray cans and refrigerants as nonflammable gases, were a significant cause of ozone depletion. A single chlorine molecule derived from CFCs can destroy approximately 100,000 molecules of ozone $\left(\mathrm{O}_3\right)$, exposing living organisms to the harmful effects of UV light.
"LPG is used for cooking. What are its constituents?
A. Propane and Benzene
B. Benzene and Butane
C. Propane and Butane
D. Only Benzene"
Solution:
The correct option is C. Propane and Butane.
LPG, or liquefied petroleum gas, primarily consists of propane and butane. These substances are highly flammable hydrocarbons and have very low boiling points, making them suitable for use as fuel in cooking and heating applications.
"Bond length of C-C in ethane (I), ethene (II), ethyne (III), and benzene (IV) follows the order:
A) I > II > III > IV B) I > II > IV > III C) I > IV > II > III D) III > IV > II > I"
The correct option is C: $$ \text{I} > \text{IV} > \text{II} > \text{III} $$
Here are the bond lengths for each compound:
- Ethane (I): $1.54 , \text{Å}$,
- Ethene (II): $1.33 , \text{Å}$,
- Ethyne (III): $1.21 , \text{Å}$,
- Benzene (IV): $1.39 , \text{Å}$.
Based on these values, ethane has the longest bond length, followed by benzene, ethene, and then ethyne, confirming that the answer is option C.
Which of the following sets contain only copolymers?
A SBR, Glyptal, Nylon-6,6
B Nylon-6, Butyl rubber, Neoprene
C Polythene, Polyester, PVC
D Melmac, Bakelite, Teflon
The correct answer is A: SBR, Glyptal, Nylon-6,6.
SBR (Styrene Butadiene Rubber), Glyptal, and Nylon-6,6 are all copolymers because they are formed from two different monomers.
- SBR is made from styrene and butadiene.
- Glyptal is created from phthalic acid and glycerol.
- Nylon-6,6 involves hexamethylenediamine and adipic acid.
It's important to highlight that copolymerization involves combining more than one type of monomer, but not necessarily with the elimination of a small molecule like water, which is characteristic of condensation polymers. Copolymers simply link different monomers in various configurations such as random, alternating, block, or graft chains.
$\mathrm{CH}{4}$ and $\mathrm{C}{2} \mathrm{H}_{6}$ form a homologous series, they differ by:
(A) $\mathrm{a}-\mathrm{CH}_{4}$ unit
B $\mathrm{a}-\mathrm{CH}_{2}$ unit
C $\mathrm{a}-\mathrm{CH}$ unit
D None of the above
Solution
The correct option is B a $-\mathrm{CH}_{2}$ unit.
A homologous series is defined as a sequence of compounds that have similar chemical properties and the same functional group but differ in composition by a constant unit - in this case, a $-\mathrm{CH}_{2}$ unit. Each successive compound in a homologous series typically differs by an additional methylene group ($-\mathrm{CH}_{2}$). Thus, between $\mathrm{CH}_{4}$ (methane) and $\mathrm{C}_{2} \mathrm{H}_{6}$ (ethane), the difference is exactly one methylene group, confirming option B as the correct answer.
Of the given forms of hydrogen, which is the most stable:
A. Occluded Hydrogen
B. Molecular Dihydrogen
C. Nascent Hydrogen
D. Atomic Hydrogen
Solution
The correct choice is Option B: Molecular Dihydrogen
Molecular Dihydrogen ($\mathrm{H_2}$) is the typical form in which hydrogen gas is found under standard conditions. It consists of two hydrogen atoms bonded together, forming a stable diatomic molecule. This stability arises from the strong covalent bond between the hydrogen atoms.
-
Occluded Hydrogen: This form of hydrogen occurs when hydrogen atoms are absorbed or adsorbed onto the surface of metals, often transition metals like Palladium (Pd) and Platinum (Pt). In this state, hydrogen becomes activated or more reactive compared to Molecular Dihydrogen.
-
Nascent Hydrogen: It refers to hydrogen that has been freshly generated and is in an exceptionally reactive state. However, it is important to note that nascent hydrogen cannot be isolated; it is a concept used to explain increased reactivity in certain chemical reactions. For example, hydrogen gas ($\mathrm{H_2}$) does not react with potassium permanganate ($\mathrm{KMnO_4}$), but zinc (Zn) and sulfuric acid ($\mathrm{H_2SO_4}$) can generate hydrogen in a state that reacts and decolorizes $\mathrm{KMnO_4}$ solution.
-
Atomic Hydrogen: This form of hydrogen consists of individual hydrogen atoms that are highly reactive. Atomic Hydrogen is typically found only under extreme conditions such as high temperatures (around 5000 K). It is far less stable compared to Molecular Dihydrogen due to its propensity to react quickly to form molecules or other compounds.
In summary, considering the stability among the given choices, Molecular Dihydrogen is the most stable form of hydrogen.
- The term rancidity is related to:
A) Acid rain
B) Fat and oil
C) Stomach acid
D) None of the above
The correct answer is B) Fat and oil.
Rancidity generally refers to the process where fats and oils undergo degradation upon exposure to air, light, or moisture, leading to unwanted changes in flavor, smell, and nutritional value. This degradation is primarily due to oxidation. Often to counteract rancidity, antioxidants are added to food products to prevent or delay the oxidation process.
48 (a) What are hydrocarbons? Give examples. (b) Give the structural difference between saturated and unsaturated hydrocarbons with two examples of each. (c) What is a functional group? Give examples of four different functional groups.
Solution
(a) What are hydrocarbons? Give examples.
Hydrocarbons are compounds primarily made up of carbon and hydrogen atoms. Examples include methane (CH₄) and ethane (C₂H₆).
(b) Explain the structural difference between saturated and unsaturated hydrocarbons with examples.
-
Saturated hydrocarbons only contain single bonds between carbon atoms. Examples are:
- Ethane (C₂H₆), with a structure of CH₃-CH₃.
- Propane (C₃H₈), with a structure of CH₃-CH₂-CH₃.
-
Unsaturated hydrocarbons contain at least one double or triple bond between carbon atoms. Examples include:
- Ethene (C₂H₄), with a double bond structure: CH₂=CH₂.
- Ethylene (C₂H₂), featuring a triple bond: CH≡CH.
(c) What is a functional group? Give examples of four different functional groups.
A functional group is a specific group of atoms within a molecule that is responsible for the characteristic chemical reactions of that molecule. Examples include:
- Hydroxyl group (-OH), found in alcohols.
- Aldehyde group (-CHO), present in aldehydes.
- Carboxyl group (-COOH), characteristic of carboxylic acids.
- Ketone group (C=O), defining feature of ketones.
A mixture of hydrazine and hydrogen peroxide is:
A. Antiseptic
B. Germicidal
C. Insecticide
D. Rocket fuel
Solution
The correct answer is D. Rocket fuel.
Hydrazine and hydrogen peroxide form a hypergolic propellant combination used in rocket engines. These components spontaneously ignite when they come into contact with each other, making them highly effective as rocket fuel.
The values of the Henry's law constant for $\mathrm{Ar}$, $\mathrm{CO}{2}$, $\mathrm{CH}{4}$, and $\mathrm{O}_{2}$ in water at $25^{\circ}$C are 40.30, 1.67, 0.41, and 34.86 kbar, respectively. The order of their solubility in water at the same temperature and pressure is
A) $\mathrm{Ar} > \mathrm{O}{2} > \mathrm{CO}{2} > \mathrm{CH}_{4}$
B) $\mathrm{CH}{4} > \mathrm{CO}{2} > \mathrm{Ar} > \mathrm{O}_{2}$
C) $\mathrm{CH}{4} > \mathrm{CO}{2} > \mathrm{O}_{2} > \mathrm{Ar}$
D) $\mathrm{Ar} > \mathrm{CH}{4} > \mathrm{O}{2} > \mathrm{CO}_{2}$
Solution
The correct answer is Option C: $\mathrm{CH}{4}>\mathrm{CO}{2}>\mathrm{O}_{2}>\mathrm{Ar}$.
According to Henry's Law, the solubility of a gas in a liquid at a constant temperature is given by:
$$ \mathrm{P}{\text {gas }} = \mathrm{K}{\mathrm{H}} \times \mathrm{X}_{\text {gas }} $$
where
- $\mathrm{P}_{\text{gas}}$ is the partial pressure of the gas above the liquid,
- $\mathrm{K}_{\mathrm{H}}$ is Henry's law constant,
- $\mathrm{X}_{\text{gas}}$ is the mole fraction of the gas in the liquid.
The relationship between the mole fraction of the gas $(\mathrm{X}{\text{gas}})$, which is proportional to the solubility of the gas in the liquid, and $\mathrm{K}{\mathrm{H}}$ is:
$$ \mathrm{X}{\text{gas}} \propto \text{solubility of gas} \propto \frac{1}{\mathrm{K}{\mathrm{H}}} $$
Given the values of $\mathrm{K}{\mathrm{H}}$ for $\mathrm{Ar}, \mathrm{CO}{2}, \mathrm{CH}{4}$, and $\mathrm{O}{2}$ as $40.30$, $1.67$, $0.41$, and $34.86$ kbar respectively, we can find the order of solubility by comparing the inverses of these constants. The lower the value of $\mathrm{K}_{\mathrm{H}}$, the higher the solubility.
Thus, the solubility order is:
$$ \mathrm{CH}{4} > \mathrm{CO}{2} > \mathrm{O}_{2} > \mathrm{Ar} $$
This order is because $\mathrm{CH}{4}$ has the smallest Henry's law constant, indicating the highest solubility, followed by $\mathrm{CO}{2}$, $\mathrm{O}{2}$, and finally $\mathrm{Ar}$, which has the highest $\mathrm{K}{\mathrm{H}}$, indicating the lowest solubility.
Emissions from motor vehicles contain:
A. Hydrocarbons
B. $\mathrm{CO}$
C. Lead
D. All of these
The correct answer is:
D. All of these
Emissions from motor vehicles include a variety of pollutants:
- Hydrocarbons (HC): These are organic compounds of hydrogen and carbon which originate from unburnt fuel.
- Carbon Monoxide (CO): Produced from the incomplete combustion of fuel.
- Lead: This is a heavy metal previously used heavily in gasoline, though now largely phased out in many countries, it still can be emitted by older vehicles or certain types of aviation fuels.
In general, vehicle emissions are complex mixtures which also contain primary gases like nitrogen, water vapor, and carbon dioxide. The harmful components, however, notably include carbon monoxide, hydrocarbons, nitrogen oxides, and particulate matter such as lead among others. These compounds are significant as they have various environmental and health impacts.
1 How many structural isomers can you draw for pentane?
Structural isomerism or constitutional isomerism involves isomers having the same molecular formula but differing in how their atoms are connected. For pentane (C$5$H${12}$), there are three structural isomers:
- n-pentane
- Isopentane (commonly known as 2-methylbutane)
- Neopentane (also known as 2,2-dimethylpropane)
These variations, having distinct structures, are tied only to the differences in branching of the carbon atoms. Each of these isomers exhibits unique physical and chemical properties due to the variance in their structures. Thus, there are 3 structural isomers of pentane.
What is the ratio of hydrogen atoms present in hept-2-yne to that in but-2-ene?
(A) 3:2 (B) 3:4 (C) 5:2 (D) 6:5
The correct answer is (A) 3:2.
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Hept-2-yne: This is an alkyne, characterized by a triple bond. Alkynes follow the general formula: $$ \mathrm{C}n \mathrm{H}{2n-2} $$ For hept-2-yne (where 'hept' implies 7 carbon atoms), substituting $n = 7$ gives: $$ \mathrm{H}{(2 \times 7) - 2} = \mathrm{H}{14 - 2} = \mathrm{H}_{12} $$ Therefore, hept-2-yne has 12 hydrogen atoms.
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But-2-ene: This is an alkene, characterized by a double bond. Alkenes use the general formula: $$ \mathrm{C}n \mathrm{H}{2n} $$ For but-2-ene (where 'but' indicates 4 carbon atoms), substituting $n = 4$ gives: $$ \mathrm{H}{2 \times 4} = \mathrm{H}{8} $$ Therefore, but-2-ene has 8 hydrogen atoms.
The ratio of hydrogen atoms in hept-2-yne to but-2-ene is calculated as follows: $$ \frac{12}{8} = \frac{3}{2} $$
Thus, the ratio is 3:2, making answer (A) 3:2 the correct choice.
Identify the gas that is chemically inert.
A) Helium
B) Hydrogen
C) Oxygen
D) Fluorine
The correct answer is A) Helium.
Noble gases are renowned for their chemical inertness due to their complete electron shells. Among the options provided, helium is the only element that is classified as a noble gas, and it is found in Group 18 of the periodic table. This makes it chemically inert.
Why do we classify hydrocarbons as saturated and unsaturated?
Hydrocarbons are classified as saturated and unsaturated based on the types of chemical bonds present between the carbon atoms within their molecular structure. Hydrocarbons containing only single bonds between carbon atoms are labeled as saturated. In contrast, those that include double or triple bonds between carbon atoms are termed unsaturated.
This classification is significant due to the differing properties of saturated and unsaturated hydrocarbons. Saturated hydrocarbons are named so because they 'saturate' the carbon with single bonds, allowing no further bonds to other carbon atoms or elements. They also generally exhibit different reactivities and participate in various chemical reactions in contrast to unsaturated hydrocarbons, which can engage in additional reactions due to their double or triple bonds.
The distinction in bonding affects both the physical and chemical properties of the hydrocarbons, such as their reactivity with substances like alcohols and halides, leading to their classification into these two groups.
Why do we consider hydrogen as the future of our energy requirements?
A. Abundant because the gas can be produced from water, and there is no $\mathrm{CO}_{2}$ as exhaust.
B. Substitution for oil, and no $\mathrm{CO}_{2}$ as exhaust.
C. High efficiency fuel and no $\mathrm{CO}_{2}$ as exhaust.
D. All of the above given choices.
Solution
The correct option is D. All of the above given choices.
Hydrogen is seen as a pivotal fuel for the future, primarily due to:
- Its capability to be produced from water, making it a highly abundant resource.
- It results in no direct $\mathrm{CO}_2$ emissions, presenting a significant advantage in reducing environmental pollution.
- Hydrogen can effectively substitute for oil, offering a sustainable alternative.
- It offers high energy efficiency (ranging from 40% to 60%), making it an efficient fuel option.
When dilute hydrochloric acid is heated with iron-sulphide, a gas with a rotten egg smell is evolved. This gas is:
A. hydrogen
B. hydrogen sulphide
C. sulphide
D. oxygen
Solution
The correct answer is: B. hydrogen sulphide
When dilute hydrochloric acid is heated with iron sulphide, a gas known for its characteristic rotten egg smell is produced. This gas is hydrogen sulphide. The reaction can be represented by the following chemical equation:
$$ \text{Iron sulphide (solid) + Dilute hydrochloric acid (solution)} \rightarrow \text{Iron chloride (solution) + Hydrogen sulphide (gas)} $$
The hydrogen sulphide gas ($\text{H}_2\text{S}$) is what you detect as having a rotten egg smell.
Noble gases are obtained by the fractional distillation of liquid air.
A) True
B) False
Solution
The correct answer is A) True.
Noble gases, which include helium, argon, neon, and others, are present in the atmosphere in minimal quantities. These gases are indeed extracted using the fractional distillation of liquid air, a process that separates these gases based on their different boiling points. Thus, the statement is true.
The number of $\mathrm{sp}^{2}$ hybrid orbitals in a molecule of benzene is:
A) 18
B) 24
C) 6
D) 12
Solution
The correct answer is Option A: 18.
Benzene (chemical formula $C_6H_6$) consists of six carbon atoms, each of which is $\mathrm{sp}^2$ hybridized. Each of these carbon atoms is involved in forming three sigma bonds ($\sigma$-bonds) through $\mathrm{sp}^2$ orbitals and one pi bond ($\pi$-bond) using the leftover p orbital.
Given that there are three $\mathrm{sp}^2$ hybrid orbitals per carbon atom for forming sigma bonds, and with six carbon atoms present, the calculation for the total number of $\mathrm{sp}^2$ hybrid orbitals is:
$$ 6 \text{ carbons} \times 3 \text{ orbitals/carbon} = 18 \text{ orbitals} $$
Thus, there are 18 $\mathrm{sp}^2$ hybrid orbitals in a molecule of benzene.
(a) What are hydrocarbons? Explain with examples. (b) Explain the meaning of saturated and unsaturated hydrocarbons with two examples each. (c) Give the names and structural formulae of one saturated cyclic hydrocarbon and one unsaturated cyclic hydrocarbon. (d) Give one example of a hydrocarbon, other than pentane, having more than three isomers. (e) How many isomers of the following hydrocarbons are possible? (i) $\mathrm{C}{3}\mathrm{H}{8}$ (ii) $\mathrm{C}{4}\mathrm{H}{10}$ (iii) $\mathrm{C}{5}\mathrm{H}{12}$ (iv) $\mathrm{C}{6}\mathrm{H}{14}$
Solution
(a) What are hydrocarbons?
Hydrocarbons are compounds composed solely of hydrogen and carbon elements. The molecular formulas (like $\mathrm{CH_4}$ for methane or $\mathrm{C_8H_{18}}$ for octane) clearly identify these elements as the only constituents.
(b) Saturated and Unsaturated Hydrocarbons:
-
Saturated hydrocarbons are those in which all carbon-carbon bonds are single covalent bonds. They are also known as alkanes and follow the general formula $\mathrm{C}n\mathrm{H}{2n+2}$, where $n$ is the number of carbon atoms.
-
Examples:
- Methane ($\mathrm{CH}_4$)
- Butane ($\mathrm{C}4\mathrm{H}{10}$)
-
Examples:
-
Unsaturated hydrocarbons consist of carbon-carbon double or triple bonds. Alkenes have at least one double bond and follow the general formula $\mathrm{C}n\mathrm{H}{2n}$, while alkynes have at least one triple bond, following $\mathrm{C}n\mathrm{H}{2n-2}$.
-
Examples:
- Ethene (an alkene): $\mathrm{C}_2\mathrm{H}_4$
- Ethyne (an alkyne): $\mathrm{C}_2\mathrm{H}_2$
-
Examples:
(c) Cyclic Hydrocarbons:
-
Saturated cyclic hydrocarbon:
- Cyclohexane ($\mathrm{C}6\mathrm{H}{12}$) is a typical example.
-
Unsaturated cyclic hydrocarbon:
- Benzene ($\mathrm{C}_6\mathrm{H}_6$) represents this category as it contains double bonds within the ring structure.
(d) Example of a hydrocarbon with more than three isomers:
-
Hexane ($\mathrm{C}6\mathrm{H}{14}$) has five structural isomers:
- normal hexane
- 2-methylpentane
- 3-methylpentane
- 2,2-dimethylbutane
- 2,3-dimethylbutane
(e) Isomers for given hydrocarbons:
-
(i) $\mathrm{C}_3\mathrm{H}_8$ (Propane):
- No isomers; propane does not allow for structural isomerism.
-
(ii) $\mathrm{C}4\mathrm{H}{10}$ (Butane):
- Two isomers: butane and 2-methylpropane.
-
(iii) $\mathrm{C}5\mathrm{H}{12}$ (Pentane):
- Three isomers: pentane, 2-methylbutane, and 2,2-dimethylpropane.
-
(iv) $\mathrm{C}6\mathrm{H}{14}$ (Hexane):
- Five isomers, matching the types listed in part (d).
Q80. Consider the following statements about Hydrogen-enriched CNG:
- HCNG may be used as a fuel for Internal Combustion Engines (ICE).
- It is considered a cleaner source of fuel, more powerful, and offers better mileage than even CNG.
- India will be the first country to begin trials with it as a fuel.
Which of the above statement(s) is/are correct?
(a) Only 1 and 2 (b) Only 2 and 3 (c) Only 1 (d) All of the above
The correct answer is (a) Only 1 and 2.
Here’s why:
- HCNG can indeed be used as a fuel for Internal Combustion Engines (ICE). This makes statement 1 correct.
- HCNG is considered a cleaner and more powerful source of fuel compared to CNG, and also offers better mileage. This confirms statement 2 as correct.
- Trials of HCNG have been conducted in multiple countries like the USA, Brazil, and South Korea, thus India is not the first country to begin trials with it as a fuel. This makes statement 3 incorrect.
As a result, the correct option is (a) Only 1 and 2.
Which of the following bioremediation methods can be used to clear oil spills in oceans?
A Chemicals that can degrade oil can be used.
B Scooping out oil using skimmers.
C Alcanivorax can be used to degrade oil.
D Rhizobium can be used to degrade oil.
The correct answer is C. Alcanivorax can be used to degrade oil.
Bioremediation utilizes living organisms, typically microbes, to remove or neutralize contaminants from a polluted area. Among these organisms, Alcanivorax is a bacterium notably effective in breaking down oil. This microbe targets oil, degrading it into non-toxic substances, making it an ideal solution for tackling oil spills in oceanic environments.
The rate of effusion of LPG (a mixture of $n$-butane and propane) is 1.25 times that of $\mathrm{SO}_{3}$. Hence, the mass fraction of $n$-butane in LPG is:
A. 0.75
B. 0.25
C. 0.50
D. 0.67
The correct answer is C. 0.50.
Given the effusion rate of LPG is 1.25 times that of $\mathrm{SO}_3$, we can use Graham's law of effusion which relates the rates of effusion of gases to the inverse square root of their molar masses:
$$ \frac{r_{\text{LPG}}}{r_{\text{SO}3}} = \sqrt{\frac{M{\text{SO}3}}{M{\text{LPG}}}} = 1.25 $$
Here, $M_{\text{SO}_3}$ (the molar mass of sulfur trioxide) is 80 g/mol. By squaring both sides of the equation, we have:
$$ \left(\frac{r_{\text{LPG}}}{r_{\text{SO}3}}\right)^2 = \left(1.25\right)^2 = \frac{M{\text{SO}3}}{M{\text{LPG}}} \Rightarrow \frac{80}{M_{\text{LPG}}} = 1.5625 $$
This leads us to find the molar mass of LPG: $$ M_{\text{LPG}} = \frac{80}{1.5625} \approx 51.2 \text{ g/mol} $$
Assuming LPG is a binary mixture of $n$-butane and propane with molecular masses $M_1 = 58 \text{ g/mol}$ (butane) and $M_2 = 44 \text{ g/mol}$ (propane), and let's denote the mole fraction of butane in LPG as $x$. Then the average molar mass $M_{\text{LPG}}$ is given by:
$$ M_{\text{LPG}} = x \times M_{1} + (1-x) \times M_{2} $$
Substituting the known values: $$ 51.2 = 58x + 44(1 - x) $$
Simplifying the equation yields: $$ 51.2 = 58x + 44 - 44x $$ $$ 51.2 = 14x + 44 $$ $$ 7.2 = 14x $$ $$ x = \frac{7.2}{14} \approx 0.514 $$
Thus, the mass fraction of $n$-butane in LPG is approximately 0.50, confirming that the right choice is C. 0.50.
If the number of hydrogen atoms in an alkene is 16, then what is the name of this hydrocarbon compound?
A. Hexene
B. Octene
C. Heptene
D. Decene
The correct option is B: Octene
The general formula for alkenes is $\mathrm{C}{\mathrm{n}} \mathrm{H}{2\mathrm{n}}$, indicating that the number of hydrogen atoms is twice the number of carbon atoms.
Given the number of hydrogen atoms is 16, from the general formula: $$ 2n = 16 $$ Solving for $n$: $$ n = \frac{16}{2} = 8 $$
Therefore, there are 8 carbon atoms in this alkene.
Thus, the name of the compound is Octene, where "oct" signifies the eight carbon atoms, and "ene" classifies it within the alkene family.
The name of the compound in the above image is 1-Propene.
Option 1: Prop-1-ene
Option 2: 1-Propene
Option 3: 1-Propene
Option 4: Prop-2-ene
The correct options are:
A Prop-1-ene
B 1-Propene
The compound in question has a three-carbon chain and contains a double bond. This compound is known as Propene, which can also be correctly represented as 1-Propene or Prop-1-ene.
Natural gas is mostly made up of:
Methane
Propane
Butane
LPG
The correct option is A. Methane
Natural gas is primarily composed of hydrocarbons such as methane, ethane, and propane. Among these, methane constitutes the major percentage of natural gas, while the others are present in smaller amounts.