Metallurgy – Download Science Study Notes Free PDF For REET/UTET Exam

EVS/ Science Study Notes Free PDF

In many teaching exams including  REETUTET DSSSB Exams etc. Science may be an interesting subject having and 30 questions of Science content and 30 questions of Science Pedagogy in REETUTET  and other State TET Exams. Science comprising of various branches of studies like chemistry, physical science, and life science.

Get free Study material for REET Exam

METALLURGY

The process of obtaining a pure metal from its ores is called metallurgy and various steps involved in the extraction are called metallurgical operations.

These operations depend upon the activity of metals. A more reactive metal (like Na, K, Mg, Ca, Al etc.) is obtained by the electrolysis of its salt in molten state, e.g., sodium is obtained by the electrolysis of fused sodium chloride. Following steps are involved in case of moderately and less reactive metals.

Practice REET Previous Year EVS Quiz For REET Exam Here

GET COMPLETE EVS STUDY NOTES HERE

  • Ore Concentration:

The removal of impurities from the ore is called its concentration.

It is carried out by the following methods:

(a) Gravity separation or hydraulic washing:  This method is generally used for the concentration of oxide ores. Powdered ore is agitated with a running stream of water. The lighter gangue particles are taken away by water while heavier ore particles settle down.

(b) Froth floatation process: This method is generally used for the concentration of sulphide ores. In this process, powdered ore is put in a tank containing a mixture of water and pine oil. When compressed air is blown into the mixture, it gets agitated and forms froth. The ore particles stick to the froth which floats on the top and can be separated easily. The gangue particles are left behind.

GET SCIENCE STUDY NOTES HERE

(c) Magnetic separation: This method is used when one component either the ore or the impurity is magnetic in nature e.g., Wolframite (magnetic) is separated from the non-magnetic ore cassiterite (SnO2) by this method.

(d) Leaching: In this method, concentration is done by chemical methods, i.e., by using chemical reagents, gold and silver are concentrated by this method. Aluminium is also obtained by this method.

(e) Roasting: In this method, concentrated ore is heated in excess of air. It involves conversion of sulphide ores into oxides and oxidation of impurities. e.g.

(f) Calcination In this method, the concentrated ore is heated in a reverberatory furnace below its melting point, in the absence of air without addition of any external substance calcination is mainly done in case or carbonate of hydroxide ores.

How To Score 25+ in Science For TET Exam

  • Corrosion:

The wasting away of metals layer-by-layer due to the formation of metal compounds on the surface is called Corrosion. Corrosion in case of iron is called rusting. The presence of air (oxygen) and water is essential for rusting.

Corrosion of metals can be prevented by painting, greasing, galvanization (coating with zinc), electroplating and alloying.

  • Alloys: A mixture of two more metals is called alloy. Some important alloys and their uses are tabulated below.

Some Important Alloys and Their uses

S. no.

Alloy

Constituent element

Use

1. Alloys of copper

i.         Brass

ii.       Bronze

iii.     German silver

iv.     Sterling silver

Copper and zinc

Copper and tin

Copper, zinc and nickel

Copper and silver

Screw wires, cooking utensils, machine parts, ornaments, musical instruments Coins, cooking utensils, ornaments, medals etc.

Silver ware, electroplating etc. Jewellery, silver ware etc.

2. Alloys of iron

v.       Steel

vi.     Stainless steel

Iron and carbon

Iron, chromium, nickel and carbon

Construction of railway lines, ships, bridges, machines etc.

Cutlery, cooking utensils, surgical instruments etc.

3. Alloys of aluminium

i.            Duralumin

ii.             Magnalium

iii.           Alnico

Aluminium, copper, magnesium, manganese

Aluminium, magnesium

Aluminium, nickel, cobalt, iron

Making the aircraft parts, space satellite

Aeroplane parts

Making magnets

4. Alloy of lead

Solder

Lead and tin Soldering joints etc.
5. Alloy of nickel

Nichrome

Nickel, iron, chromium and manganese Electrical heating elements
6. Alloy of mercury Amalgam Mercury, silver, tin and zinc Teeth filling

Download Science Study Notes – In English

Download Science Study Notes PDF – हिंदी में

Download Upcoming Government Exam Calendar 2021

×

Download success!

Thanks for downloading the guide. For similar guides, free study material, quizzes, videos and job alerts you can download the Adda247 app from play store.

Thank You, Your details have been submitted we will get back to you.
×
Login
OR

Forgot Password?

×
Sign Up
OR
Forgot Password
Enter the email address associated with your account, and we'll email you an OTP to verify it's you.


Reset Password
Please enter the OTP sent to
/6


×
CHANGE PASSWORD