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Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

In the refining of petroleum, in a fractionating column, the principle used is _______.

  1. difference in melting point

  2. difference in boiling point

  3. difference in freezing point

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

A fractionating column is an essential thing which is used in distillation of liquid mixtures so as to separate the mixture into its component parts, or fractions, based on the differences in their boiling temparatures. Fractionating columns are used in small scale laboratory distillation process as well as for large scale industrial distillations.

Hence option B is correct.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

Which step is not present in the extraction of petroleum?

  1. Pumping

  2. Drilling

  3. Distillation

  4. Seismic survey
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Procedure for extraction of petroleum:

i) Locating the oil field or seismic survey
ii) Drilling
iii) Oil extraction and recovery ( involves pumping)
Distillation is used for extracting different petroleum products like petrol, diesel, natural gas from petroleum.
Hence, the correct option is $C$.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

________ is a process by which components in a chemical mixture are separated into different parts according to different boiling points in a fractionating column.

  1. Vacuum distillation

  2. Steam distillation

  3. Fractional distillation

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Vacuum distillation is a distillation of a liquid under reduced pressure, enabling it to boil at a lower temperature than normal.

Steam distillation of a liquid in a current of steam used especially to purify liquids that are not very volatile and are immiscible with water.

Fractional distillation is a separation of a liquid mixture into fractions differing in boiling point (and hence chemical composition) by means of distillation, typically using a fractionating column.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

Petroleum refining involves:

  1. vacuum distillation

  2. steam distillation

  3. fractional distillation

  4. fractional crystallisation
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The various fractions of petroleum are separated by fractional distillation.
Fractional distillation is one separation of a mixture into its components parts, or fractions, sour as in separating chemical compounds by their boiling point by heating them to a temp at which one or more fractions of the compound will vaporize.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

During fractional distillation of petroleum, different fractions are obtained. Their name, number of carbon atoms, temperature range at which it is obtained, their uses are given. There is an error in one of the alternatives. In which alternative there is an error?

  1. Petrol, ${ C } _{ 5 }to{ C } _{ 10 }$, 303K to 393K, fuel in vehicles.
  2. diesel, ${ C } _{ 15 }to{ C } _{ 18 }$, 533K to 613K, fuel in vehicles and generators.
  3. Neptha, ${ C } _{ 8 }to{ C } _{ 10 }$, 393K to 453K, solvent in petro chemicals.
  4. lubricating oil, ${ C } _{ 8 }to{ C } _{ 12 }$, 400K, fuel in high speed vehicles.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Lubricating oil,$C _{16}$ to $C _{20}$ above 613K is used as lubrication oil in machine and to prepare grease,vaseline etc.

 Therefore,lubricating oil $C _8$ to $C _{12}$,400K fuel in high speed vehicles is the correct answer.
Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

The process of crystallization is used to obtain pure solids because:

  1. iIt is better than evaporation

  2. impurities are filtered completely

  3. ultra pure crystals are formed

  4. decomposition does not take place
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Since crystallization generally produces salts which are crystalline in state or $100$ percent purity in state.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

What is the method to separate two compounds with different solubilities in a solvent? 

  1. Sublimation

  2. Crystallization

  3. Chromatography

  4. Distillation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Two compounds which have different solubilities in a solvent S can be separated from each other by Fractional Crystallisation. The process involves a series of repeated-crystallisations. The mixture of the two compounds in the solvent S is heated so as to make it saturated. When the hot solution is allowed to cool, the less soluble substance crsytallises out first while the more soluble substance remains in the solution. The crystals of first compound are separated from the mother liquor and the mother liquor is again concentrated and allowed to cool when the crystals of the 2nd compound are obtained.

Multiple choice chemistry world energy needs coal petroleum non-renewable sources of energy

Separation of a mixture into its components, whose boiling points are different, is called :

  1. fractional distillation

  2. destructive distillation

  3. displacement

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

Separation of a mixture into its components whose boiling points are different is called Fractional distillation.
This method is used for separating a mixture of two or more volatile liquids both having close boiling points. The boiling points of two components differ by 10-15 K. For example, acetone and methanol with boiling points 329 K and 338 K can be separated  by this method. This method is used for distillation of petroleum, coal tar and crude alcohol.