Tag: study of kerala

Questions Related to study of kerala

A solution is a homogeneous mixture of two or more substances. Which of the following is a solution?

geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. Milk

  2. Smoke

  3. Brass

  4. Face Cream

Show answer
Correct Option: C
Explanation:

Alloys are the homogeneous mixture of metals or metals and non metals. Brass is an alloy of copper and zinc
Brass $Cu-70$%
$Zn-30$%
Alloys are solid-solid solution

Heating a pyrite in air to remove sulphur is known as:

geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. smelting

  2. roasting

  3. bessemerisation

  4. calcination

Show answer
Correct Option: B
Explanation:

Roasting is a process of heating of sulphide ore to a high temperature in the presence of air. It is a step of the processing of certain ores.


Hence, option B is correct.

Which of the following is the ore of $Cu$?

geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. Ciderite

  2. Magnetite

  3. Calamine

  4. Malachite

Show answer
Correct Option: D
Explanation:

Ore of copper is malachite $CuCO _{3}.Cu(OH) _{2}$.

The ore that can be concentrated by magnetic separation method is:

geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. bauxite $(Al _{2}O _{3}.xH _{2}O)$

  2. pyrolusite $(MnO _{2})$

  3. cuprite $(Cu _{2}O)$

  4. zincite $(ZnO)$

Show answer
Correct Option: B
Explanation:

The ore that can be concentrated by magnetic separation method is pyrolusite $(MnO _{2})$.
In this method, the ferromagnetic and non-magnetic particles in the ore are separated by an electromagnetic separator.

The waste, or slag, that comes out at the bottom of a blast furnace for making iron from its ore, is no thrown away. It is used for making?

geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. Dental powder

  2. Roads

  3. Plastics

  4. Glass moulds

Show answer
Correct Option: B
Explanation:

Solution:- (B) Roads

Slag is valuable raw material for preparation of macadam materials and mineral blinders serving as a base for asphalt concrete mixture and manufacturing of cement emulsions, which are widely used in road paving.

Match the columns.

List I List II
A. Bauxite $1.$ Lead
B. Haematite $2.$ Thorium
C. Galena $3.$ Aluminium
D. Monazite $4.$ Iron
geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. $A - 3, B - 1, C - 4, D - 2$

  2. $A - 4, B - 2, C - 1, D - 3$

  3. $A - 3, B - 4, C - 1, D - 2$

  4. $A - 2, B - 4, C - 3, D - 1$

Show answer
Correct Option: C
Explanation:

Solution:- 

(A) Bauxite $\rightarrow \left( {Al} _{2}{O} _{3}.2{H} _{2}O \right)$ It is an ore of Aluminium containing $15-20 \%$ aluminium. $\rightarrow$ (3) Aluminium
(B) Haematite $\rightarrow \left({Fe} _{2}{O} _{3} \right)$ A reddish-black mineral consisting of ferric oxide. It is an important ore of iron. $\rightarrow$ (4) Iron
(C) Galena $\rightarrow \left( PbS \right)$ Galena, also called lead glance, is the natural mineral form of lead(II) sulfide. $\rightarrow$ (1) Lead
(D) Monazite $\rightarrow$ Monazite is an important ore for thorium, lanthanum, and cerium. It is radioactive due to the presence of thorium. $\rightarrow$ (2) Thorium

Pig iron can be converted into steel by removing a lot of carbon contained in it, in a/ an:

geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. electrolytic chamber

  2. bessemer converter

  3. blast furnace

  4. pyrite burner

Show answer
Correct Option: B
Explanation:

Solution:- (B) bessemer converter

The Bessemer process was the first inexpensive industrial process for the mass production of steel from molten pig iron before the development of the open hearth furnace. The key principle is removal of impurities from the iron by oxidation with air being blown through the molten iron.

The removal of unwanted impurities by mechanical methods is known as:

geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. finishing

  2. ore dressing

  3. smelting

  4. none of these

Show answer
Correct Option: B
Explanation:

As dressing is the process which have extraction and dressing. So, unwanted materials are removed through this method.

In manufacture of iron from Haematite, lime stone is added is act as:

geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. slag

  2. an oxidizing agent

  3. a reductant

  4. flux

Show answer
Correct Option: D
Explanation:

Lime stone in the manufacture of Hematite ore is called flux. It removes unwanted material combining with gangue. 

Calcium silicate slag formed in extraction of iron :

geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

  1. prevents the reoxidation of molten iron.

  2. catalyses the combustion of carbon

  3. reduces $CO _2$ to $CO$ at the bottom of the furnace

  4. is used in cement industry

Show answer
Correct Option: A,D
Explanation:

Slag formed in extraction of iron is consists of $CaSiO _3$ which is further used for making cement.
Also, formation of this slag prevents the re-oxidation of molten iron.