Tag: study of kerala

Questions Related to study of kerala

The combined state of metals are called:

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

  1. Mineral

  2. Gangue

  3. Flux

  4. Native form

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Correct Option: B
Explanation:

The metal found in nature occur in the free or combined state it is generally known as pure metals. A native metal is a metal found in metallic state naturally.  It can be in the pure form or in the form of an alloy.


$Mineral:$  Minerals are substances that are formed naturally in the earth.  Minerals are usually solid, inorganic, have a crystal structure, and are formed naturally by geological process.


$Gangue:$ It is sand, rock and other impurities surrounding the minerals of interest in an ore. It is the combined state of the metal.

$Flux:$ It is a chemical cleaning, flowing or purifying agent.  It is the substance added to the molten metals to bond with impurities that can be removed.

$Native form:$ Native element, any number of chemical elements that may occur in nature uncombined with other elements.


Hence, the correct option is B.

Which is not a step of metallurgy ? 

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

  1. Reduction

  2. Roasting

  3. Corrosion

  4. Concentration of ore

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Correct Option: C

Sulphide ores are common for metals:

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

  1. Ag, Cu and Pb

  2. Ag, Cu and Sn

  3. Ag, Mg and Pb

  4. none

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Correct Option: A
Explanation:

  1. Argentite $Ag _2S$
  2.  Galena $PbS$
  3.  Chalcocite $Cu _2S$
  4.  Copper pyrite (chalco pyrite)$ [CuFeS _2]$
  5.  Cassiiterite $SnO _2$
  6.  Dolomite  [$ Ca Mg (CO _3) _2$]
  7.  Bauxite $Al(OH) _3$

∴ Sulphide containing ores are$ Ag, Cu, Pb.$


Option A is correct.

Which of following metal is extracted by electrometallurgical method-

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

  1. $Cu$

  2. $Fe$

  3. $Na$

  4. $Ag$

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Correct Option: A,C
Explanation:

electrometallurgical method is used for the extraction of metals which are reactive in nature.

example. sodium,copper,aluminium and many more.

The pair that does NOT required calcination is :

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

  1. ZnO and $Fe _{2}O _{3}.xH _{2}O$

  2. $Fe _{2}O _{3}$ and $CaCO _{3}.MgCO _{3}$

  3. $ZnCO _{3}$

  4. ZnO and MgO

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Correct Option: D

Which of the following is a basic carbonate mineral?
(i) Malachite  (ii) Dolomite  (iii) Azurite  (iv) Magnesite

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

  1. (i), (iii) and (iv)

  2. (II), (iii) and (iv)

  3. (i) and (iv)

  4. (iii) and (iv)

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Correct Option: B

The process(es) by which lighter earthy particles are freed from the heavier particles using water is/are:

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

  1. Gravity separation

  2. Levigation

  3. Hydraulic washing

  4. Leaching

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Correct Option: A,B,C
Explanation:

During concentration of ores, lighter earthy particles are freed from the heavier particles using water. This is carried out by gravity separation or hydraulic washing or levigation.
During leaching, the soluble material is extracted from insoluble material by dissolving out in a suitable solvent.

Which of the following mixture can be separated by magnetic separation?

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

  1. Iron filings, sand and iodine

  2. Common salt, sand and marbles

  3. Chalk powder, grain and chaff

  4. Stone, salt and water

Show answer
Correct Option: A
Explanation:
For option A, the iron filling can be removed by using a magnet. an iron filling will be attracted by a magnet while water and iodine will not.

For option B, marbles can be separated by hand. Now add water salt will dissolve while sand will not. then separate the saltwater and sand.

For option C, winnowing can be used to separate chaff and grains.for chalk powder we can use filtration.

For option D, stone can be removed by handpicking, now water and salt can be separated by boiling the water. so water will evaporate leaving salt behind.

Match the following:


(i) Biodegradable polymer (p) 3-Hydroxybutanoic acid
(ii) Bakelite (q) Phenol
(iii) Neoprene (r) 2-chlorobuta-1, 3-diene
(iv) Glyptal (s) phthalic acid

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

  1. $i - p, ii - q, iii - r, iv - s$

  2. $i - q, ii - p, iii - r, iv - s$

  3. $i - p, ii - q, iii - s, iv - r$

  4. $i - s, ii - r, iii - p, iv - q$

Show answer
Correct Option: A
Explanation:

(i) PHBV (3-Hydroxybutanoic acid + 4-Hydroxypentanoic acid) is a biodegradable polymer. 


(ii) Bakelite is synthesized from the monomer Phenol & Formaldehyde

(iii)  2-chlorobuta-1,3-diene is the monomer of Neoprene.

 
(iv) Glyptal is synthesized from the condensation polymerization of Phthalic acid & Ethylene glycol.

Hence, the correct option is $\text{A}$

A tin chloride $Q$ undergoes the following reaction (not balanced)
$Q + Cl^{-} \rightarrow X$
$Q + Me _{3}N \rightarrow Y$
$Q + CuCl _{2}\rightarrow Z + CuCl$
$X$ is monoanion having pyramidal geometry. Both $Y$ and $Z$ are neutral compounds. Choose the correct options(s)

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

  1. The central atom in $X$ is $sp^{3}$ hybridized

  2. There is a coordinate bond in $Y$

  3. The oxidation state of the central atom in $Z$ is $+2$

  4. The central atom in $Z$ has one lone pair of electrons

Show answer
Correct Option: A,B
Explanation:

$\underset {(P)}{SnCl _{2}} + Cl^{-} \rightarrow \underset {(X)}{SnCl _{3}^{-}}$
$\underset {(P)}{SnCl _{2}} + Me _{3}N \rightarrow \underset {(Y)}{SnCl _{2} [N(CH _{3}) _{3}]}$
$\underset {(P)}{SnCl _{2}} + 2CuCl _{2}\rightarrow \underset {(Z)}{SnCl _{4}} + CuCl$.