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

Which of the following statements is correct regarding the slag formation during extraction of a metal like copper or iron?

  1. The slag is lighter and lower melting than the metal.

  2. The slag is heavier and lower melting than the metal.

  3. The slag is lighter and higher melting than the metal.

  4. The slag is heavier and higher melting than the metal.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Slag formed in extraction of metals are lighter and having low melting point than metal so they generally appear in upper layer of solutions.

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

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

  1. Gravity separation

  2. Levigation

  3. Hydraulic washing

  4. Leaching
Reveal answer Fill a bubble to check yourself
A,B,C Correct answer
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.

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

During smelting, an additional substance is added which combines with impurities to form a fusible mass. The additional substance is called__________.

  1. Flux

  2. Slag

  3. Gangue

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

In the process of smelting, inorganic chlorides, fluorides, limestone and other materials are designated as "fluxes" when added to the contents of a smelting furnace or a cupola for the purpose of purging the metal of chemical impurities such as phosphorus, and of rendering slag more liquid at the smelting temperature.

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

$SnO _2$ is reduced to metallic Sn on smelting oxide with anthracite and lime. In this, the function of lime is :

  1. it acts as a flux

  2. it removes acidic impurities as slag

  3. it removes ,basic impurities as slag

  4. it acts as a slag
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation

In the smelting process the black Sn is mixed with anthracite and little limestone which acts as flux, now this mixture is heated to a degree centigrade of 1200-1300, as a result, $SnO _2$ is reduced to Sn. This crude is having many acid impurities which can be removed as slag.$SnO _2+2C \Rightarrow Sn+2C$.

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

Which statement is correct?

  1. Gangues are carefully chosen to combine with the slag present in the ore to produce easily fusible flux to carry away the impurities

  2. Slags are carefully chosen to combine with the flux present in the ore to produce easily fusible gangue to carry away the impurities

  3. Gangues are carefully chosen to combine with the flux present in the ore to produce easily fusible slag to carry away the impurities

  4. Fluxes are carefully chosen to combine with the gangue present in the ore to produce easily fusible slag to carry away the impurities
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Flux: The substance which is added to remove the gangue from the concentrated ore in its molten state is called Flux and the substance formed with flux is called Slag. Hence, fluxes have to be carefully chosen.

Acidic Flux
$SiO _2 + CaO \rightarrow CaSiO _3$
Acidic flux removes basic impurities.

Basic Flux
$SiO _2 + MgO \rightarrow MgSiO _3$
Basic flux removes acidic impurities
Multiple choice geography in the land of kerala introduction to metallurgy occurrence of metals study of kerala

Here an extraction process is given in steps. Identify the suitable ores corresponding to the process.
Pulverisation $\rightarrow$ Calcination $\rightarrow$ Smelting $\rightarrow$ Vacuum $\rightarrow$ Distillation

  1. Zinc blend

  2. Calamine

  3. Magnesite

  4. Zincite
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation

Zinc Sulphide and Calamine responds for the process because, in $ZnS$, only zinc comes at smelting and after process, high purity comes after distillation. similar to Calamine, after distillation, the metal obtained is pure.

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

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

  1. bauxite $(Al _{2}O _{3}.xH _{2}O)$
  2. pyrolusite $(MnO _{2})$
  3. cuprite $(Cu _{2}O)$
  4. zincite $(ZnO)$
Reveal answer Fill a bubble to check yourself
B Correct answer
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.