Chemistry · Science General

Metallurgical Processes

1,403 Questions

This section explores key metallurgical processes including ore concentration, pyrometallurgy, and metal refining. It also covers corrosion and the properties of refractory materials. These chemistry questions are relevant for engineering and science entrance tests.

Pyrometallurgy furnacesMetal refining techniquesCorrosion protection methodsOre concentrationAuto reduction process

Metallurgical Processes Questions

Multiple choice chemistry chemical changes applications of electrolysis electroplating extraction of metals by electrolysis

In the electroplating of silver, $AgNO _3$ solution is usually used as:

  1. oxidant

  2. reductant

  3. electrode

  4. electrolyte
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The process of depositing a thin layer of silver electrolytically on the metal surface is called silver plating. The article to be silver-plated is used as cathode while anode consists of pure silver. 


The bath contains a solution of potassium argentocyanide ($AgNO _3$ + excess of KCN). The complex ion is very stable and ionisation is very small at a time with the result slow and uniform deposition of silver takes place. 

$[Ag(CN) _2]^2 \rightleftharpoons Ag^+ + 2CN^-$


Hence, option D is correct.

Multiple choice chemistry chemical changes applications of electrolysis electroplating extraction of metals by electrolysis

Galvanization of iron denotes coating with:

  1. copper

  2. aluminium

  3. silver

  4. none of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Galvanization is the process of applying a protective zinc coating to steel or iron, to prevent rusting. Galvanization of Iron meaning coating with zinc.


It forms a coating of corrosion-resistant zinc which prevents corrosive substances from reaching the more delicate part of the metal. The zinc serves as a sacrificial anode so that even if the coating is scratched, the exposed iron will still be protected by the remaining zinc.

Multiple choice chemistry chemical changes applications of electrolysis electroplating extraction of metals by electrolysis

Which of the following is not an electrochemical process?

  1. Transmission of nerve impulses in human body

  2. Rusting of iron

  3. Lightning

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

Both transmission of nerve impulse and  rusting of iron are results of electrochemical reactions.In transmission of nerve impulse numerous small molecules function as neurotransmitters at various chemical synapses.Rust is an iron oxide, usually red oxide formed by the redox reaction of iron and oxygen in the presence of water or air moisture. Lightning is a sudden electrostatic discharge during an electrical storm between electrically charged regions of a cloud. 

Multiple choice chemistry chemical changes applications of electrolysis electroplating extraction of metals by electrolysis

Electro refining which is based on phenomenon of Electrolysis where:

  1. impure metal is made anode and pure metal is cathode

  2. impure metal is cathode and pure metal is anode

  3. pure metal makes both anode and cathode

  4. none of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This method is based upon the phenomenon of electrolysis. The crude metal is made anode whereas the thin sheet of a pure metal is made cathode. The electrolyte is the solution of the soluble salt of the same metal, preferably a double salt on passing electricity the metal from anode goes into solutions as ions due to oxidation while the pure metal gets deposited at the cathode due to the reduction of metal ions the impurities settle down below the anode as Anode Mud.

Multiple choice chemistry chemical changes applications of electrolysis electroplating extraction of metals by electrolysis

The main applications of electrolysis are:

  1. electroplating

  2. electrorefining

  3. extraction of metals

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The main application of electrolysis are:


Electroplating: Electroplating is a process of depositing a layer of any desired metal on another material by means of electricity.

Electrorefining: Electrorefining refers to the process of using electrolysis to increase the purity of a metal extracted from its ore.

Extraction of metals: Extractions are a way to separate the desired substance when it is mixed with others. 

Hence, option D is correct.

Multiple choice chemistry chemical changes applications of electrolysis electroplating extraction of metals by electrolysis

Silver can be spread as a thin sheet on another metal by electroplating. The film of silver sticks strongly to the metal. Which of the following metals cannot be properly plated with silver?

  1. Copper

  2. Iron

  3. Nickel

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

Iron cannot be property plated with silver it becomes peel if plated with silver are to peeling of silver it cannot properly plated iron.

Multiple choice chemistry chemical changes applications of electrolysis electroplating extraction of metals by electrolysis

In electroplating of copper by silver, the silver acts as an :

  1. anode

  2. cathode

  3. electrode

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

Silver plating on Steel spoon: A silver rod is made as anode and steel spoon as cathode. Potassiumargentocyanide $(K[Ag(CN) _2])$ is used as electrolyte.
$AgNO _3$ is not used as electrolyte because in that case the silver coating will be non-uniform as the electrolysis takes place rapidly.
In electroplating of copper by silver, silver rod is taken as anode.

Multiple choice chemistry occurrence of carbon compounds in nature substances, objects and energy alternative fuels and energy sources alternative sources of energy

Why are metal pipes not an ideal means of transport for pure hydrogen?

  1. They become brittle

  2. They burst out

  3. The metals melt

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

Pure hydrogen is the smallest element and some of it will inevitably escape from any known container or pipe in micro amounts. It causes the metal to become brittle, suggesting metal pipes may not be ideal for hydrogen transport.

Multiple choice chemistry rocks and minerals coal and its products study of coal coal

Coke is used in the manufacturing of :

  1. lead

  2. copper

  3. steel

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

Coke is used as a fuel and as a reducing agent in smelting iron ore in a blast furnace. The carbon monoxide produced by its combustion reduces iron oxide in the production of steel.