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Multiple choice methane study of methane carbon- an important element hydrocarbons chemistry

Methane reacts with chlorine in the presence of sunlight. If this reaction is allowed to continue, the end product formed will be :

  1. carbon tetrachloride

  2. chloroform

  3. ethylene chloride

  4. chalcogons
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The free-radical chlorination of methane is a chain reaction that continues until all hydrogen atoms are replaced by chlorine, resulting in carbon tetrachloride (CCl4).

Multiple choice methane study of methane carbon- an important element hydrocarbons chemistry

Bakelite is a:

  1. Urea formaldehyde resin

  2. Phenol formaldehyde resin

  3. Both A and B

  4. None
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bakelite, a trademark of phenol-formaldehyde resin, trademarked synthetic resin invented in 1907 by Belgian-born American chemist Leo Hendrik Baekeland. 

A hard, infusible, and chemically resistant plastic, Bakelite was based on a chemical combination of phenol and formaldehyde (phenol-formaldehyde resin).

Multiple choice methane study of methane carbon- an important element hydrocarbons chemistry
At room temperature and standard pressure, methane is a colorless, odourless gas.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The given statement is True.
At room temperature and standard pressure, methane is a colorless, odorless gas.
First four members are colourless, odourless gases, pentane to heptadecane are colourless, odourless liquids, while higher alkanes are colourless solids.

Multiple choice methane study of methane carbon- an important element hydrocarbons chemistry

When four moles of $O _2$ is used for complete combustion of methane.$1600kJ$ of heat is evolved.The calorific value of methane is ?

  1. $100 kJ/g$
  2. $800 kJ/g$
  3. $50kJ/g$
  4. $1600 kJ/g$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$CH _4+2O _2 \longrightarrow CO _2+2H _2O$             $\Delta H _f$

$\Rightarrow$ for $1$ mole methane   $2$ mole of oxygen is used.
$\Rightarrow$ for $2$ mole methane    $4$ mole of oxygen is used.
$\Rightarrow$ For $2$ mole $\Delta H= 1600$
$\Rightarrow$ For $1$ mole $\Rightarrow \cfrac {\Delta H}{2}=800KJ$
For $1g$ of $CH _4 \Rightarrow \cfrac {800}{16}=50KJ$

Multiple choice methane study of methane carbon- an important element hydrocarbons chemistry

Methane is a major component of :

  1. biogas

  2. producer gas

  3. natural gas

  4. All of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The main component of natural gas is methane. 

Generally, less than 5 percent of natural gas is ethane and propane. 
The main uses of methane natural gas are to generate electricity and make energy. Methane is the main component of natural gas. The combustion of methane releases energy, which is in the form of natural gas.

Multiple choice methane study of methane carbon- an important element hydrocarbons chemistry

Chlorination of methane does not occur in dark because:

  1. methane can form free radicals in presence of sunlight only
  2. to get chlorine free radicals from $Cl _2$ molecules energy is required. It cannot happen in dark.

  3. substitution reaction can take place only in sunlight and not in dark

  4. termination step cannot take place in dark. It requires sunlight.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Chlorination of methane is a free radical substitution. To get chlorine free radical, UV light is required to initiate the substitution reaction, which is provided by sunlight.
$Cl _2\xrightarrow [  ]{ hv } Cl^{\bullet}+Cl^{\bullet}$
Multiple choice methane study of methane carbon- an important element hydrocarbons chemistry

When vegetable matter decays at the bottom of lakes and ponds where there is limited air, it gives rise to 'marsh gas', which is:

  1. oxygen

  2. chlorine

  3. butane

  4. methane
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
(i) Marsh gas is a mixture of methane, hydrogen sulfide and carbon dioxide which has methane at high percentage compared to the other two compounds.
(ii) Marsh gas is produced naturally in flooded regions.
(iii) This condition allows anaerobic digestion and fermentation of organic matter which produces methane