Advertisements
Advertisements
प्रश्न
What is fractional distillation ? What is the use of fractionating column in fractional distillation ?
Advertisements
उत्तर
Fractional distillation is a process of separating two or more miscible liquids by distillation. The distillate is collected in fractions, which boil at different temperatures. The principle behind this technique is the difference in boiling points of the liquids in the mixture.
The fractionating column is fitted in the neck of the distillation flask. Fractionating column provides different temperature zones inside the flask. The highest temperature is at the bottom and the lowest temperature is near its top.
APPEARS IN
संबंधित प्रश्न
During respiration, glucose and oxygen enter our body cells and waste products carbon dioxide and water leave the body cells by the process of :
Name a non-metal which is a good conductor of electricity.
The three important metalloids are.............................. and ..........................
Define a compound. Give two points of evidence to show that sodium chloride is a compound.
A, B and C are all liquids. Liquid A has a comparatively low boiling point. On heating, liquid A vaporises completely without leaving behind any residue. Liquid A is being used increasingly as a fuel in motor vehicles either alone or by mixing with petrol. Liquid B has a very high boiling point. It also vaporises completely on heating, without leaving any residue. Liquid B is a conductor of electricity and used in making thermometers. Liquid C has a moderate boiling point. On heating, liquid C vaporises leaving behind a white solid D which is used in cooking vegetables. The condensation of vapours from C give a liquid E which turns anhydrous CuSO4 to blue.
(a) Which liquid could be an element ? Name this element.
(b) Which liquid could be a mixture ? Name this mixture.
(c) Which liquid could be a compound ? Name this compound.
(d) What could the solid D be ?
(e) What do you think is liquid E ?
State whether colloidal solutions are homogeneous or heterogeneous.
Explain what happens when a beam of light is passed through a colloidal solution.
How will you differentiate between a suspension and a colloid ?
Which of the following is not an emulsion ?
Which of the following represents the solubility of sugar in water at 20°C ?
When the solid A is added to water, it dissolves with the evolution of a lot of heat and making little explosions to form two products B and C. The properties of products B and C are entirely different from those of solid A as well as water. Moreover, products B and C cannot be reconverted into solid A and water. When another solid D is added to water, it dissolves with the absorption of a little heat to form a product E which cools down. The product E shows the properties of both, solid D as well as water. Moreover, product E can be converted into solid D and water.
(a) What type of change occurs when solid A is dissolved in water ? Why ?
(b) What type of change occurs when solid D is dissolved in water ? Why ?
(c) Name a metal which you think could behave like solid A. Also name the products B and C.
(d) Name the solid D if it is the one which is used in making ordinary dry cells.
(e) Name the process by which D can be recovered from E.
How would you obtain sodium chloride from a mixture of sodium chloride and sulphur without using water ?
How would you separate iodine from a mixture of iodine and common salt ?
Asmita went to buy an earthen pot. There she saw many things kept for sale.
What is the difference between a substance and an object?
Which among the following is not a matter?
The most reactive metal is ______.
Solid is an arrangement of particles ______.
Give an example of a molecule.
Define the term matter.
