Chemistry · Science General

Metallurgical Processes

1,436 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 non-metals introduction to non-metals occurence of metals occurrence of metals and non metals

Silver can be separated from lead by:

  1. fractional crystallization

  2. amalgamation

  3. cupellation

  4. addition of zinc
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
The Parkes process is a pyrometallurgical industrial process for removing silver from lead during the production of bullion. It is an example of liquid–liquid extraction.
The process takes advantage of two liquid-state properties of zinc. The first is that zinc is immiscible with lead, and the other is that silver is 3000 times more soluble in zinc than it is in lead. When zinc is added to liquid lead that contains silver as a contaminant, the silver preferentially migrates into the zinc. Because the zinc is immiscible in the lead it remains in a separate layer and is easily removed. 
Multiple choice chemistry non-metals introduction to non-metals occurence of metals occurrence of metals and non metals

Aluminium metal is purified by:

  1. Hoopes process

  2. Halls process

  3. Serpecks process

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

All processes are used in Aluminium metallurgy but the Hoopes process is a metallurgical process, used to obtain the aluminium metal of very high purity.
The Bayer process is the principal industrial means of refining bauxite to produce alumina (aluminium oxide).
The Hall–Héroult process is the major industrial process for smelting aluminium. 
Serpeck's process  is used for the purification of bauxite ore containing silica  as the main impurity
Multiple choice chemistry non-metals introduction to non-metals occurence of metals occurrence of metals and non metals

Heamatite ore is concentrated by:

  1. gravity separation method

  2. forth floatation

  3. amalgamation

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

Heamatite is an iron oxide with a chemical composition of $Fe _2O _3$. Gravity Separation or Hydraulic Washing (Levigation)

Heamatite ore is concentrated by gravity separation method. This method of concentration of the ore is based on the difference in specific gravities of the metallic ore and gangue particles. Generally metal ores are heavier than the gangue associated with them.
By flowing the powdered ore in a current of water, the lighter rocky impurities can be washed away and the ore particles are left behind. For this, either wilfley table or Hydraulic classifier is used. Generally oxide and carbonate ores are concentrated by this method. i.e. haematite and cerussite.

Multiple choice chemistry chemical thermodynamics system and surroundings introduction to thermodynamics basics of thermodynamics

Which of the following factors is of no significance for roasting sulphide ores to the oxides and not subjecting the sulphide ores to carbon reduction directly?

  1. Metal sulphides are thermodynamically more stable than $CS _2$
  2. $CO _2$ is thermodynamically more stable than $CS _2$

  3. Metal sulphides are less stable than the corresponding oxides
  4. $CO _2$ is more volatile than $CS _2$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The reduction of metal sulfides by carbon reduction process is not spontaneous as the change in Gibb's free energy ($\triangle G$) for such a process is positive. 

The reduction of metal oxides by carbon reduction process is spontaneous as $\triangle G$ for such a process is negative.
Thus $CO _2$ is more stable than $CS _2$ and the metal sulfides are more stable than the corresponding oxides.
Hence, factor listed in $(3)$ is of no. significance.

Multiple choice evs experiments with water water and its types hard and soft water what floats - what sinks

The brownish-white deposit on kettles, heating elements and utensils formed by boiling water is due to:

  1. moisture in the air

  2. temporary hardness of water

  3. permanent hardness of water

  4. reaction of sulphur dioxide in the air with hot water
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The temporary hardness of water is due to the presence of calcium or magnesium bicarbonates. 

The brownish-white deposit on kettles, heating elements, and utensils formed by boiling water are due to the temporary hardness of water. 
It can be removed from water by heating due to which the hydrogen carbonate decomposes to original insoluble carbonate.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Metals are usually hard. Hence metals are strong and can withstand heavy loads over them. Due to this property, they are difficult to cut and can be used in the construction of heavy machines, building etc.
On the other hand, non-metals are usually brittle. On hammering them they break into small pieces converting themselves into a fine powder.


In the following elements identify the elements that is relatively brittle?

  1. Sulphur

  2. Diamond

  3. Iron

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

Diamond is the hardest non-metallic element which is an exception. Sulphur is a non metal and is relatively brittle while others are metals and are hard, but not brittle.


Therefore, option A is correct.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

1 kg of iron occupies less space compared to 1 kg of sponge. Why?

  1. Iron has less density than sponge

  2. Iron and sponge have equal densities

  3. Iron has more density than sponge

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
We have 2 materials here in which iron is metal and Sponge is non-metal.
 Metals has usually high density as compared to non-metals.
  and Density*Volume = Mass
  Iron occupies less space because it has high density.
Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Door locks are made of metals because metals:

  1. have lustre

  2. are opaque

  3. are good conductors of heat

  4. are hard and strong
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Door locks are usually needed to be strong to stop thieves or other trespassing. 

So we need a hard and strong material for the manufacturing of locks and metals are feasible for this purpose.

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

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Mark the correct statement.
a) Metals lose their lustre on keeping in air.
b) Gold is lustrous.
c) Metals are lustrous and can be polished.

  1. a, b

  2. b, c

  3. a, c

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

Metals lose their lustre when kept exposed to air for long time and gets a dull appearance. It loses most of its shine and lustre.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Which of the following is used to galvanize metals, making them resistant to oxidation (rusting)?

  1. Zinc

  2. Iron

  3. Tin

  4. Aluminium

  5. Hydrogen
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Zinc is used to galvanize metals, making them resistant to oxidation (rusting). Zinc is stronger reducing agent than the metal to be galvanized (such as iron) and hence, zinc can be more easily oxidised. Thus, during corrosion, zinc is oxidised. This prevents corrosion (rusting) of other metal.

Multiple choice chemistry metals physical properties of metals and non-metals some physical properties of metals general characteristics and uses of metals

Metals are usually hard. Hence metals are strong and can withstand heavy loads over them. Due to this property, they are difficult to cut and can be used in the construction of heavy machines, building etc.
On the other hand, non-metals are usually brittle. On hammering them they break into small pieces converting themselves into a fine powder.


Thus an element that is relatively strong is relatively :

  1. Brittle

  2. Malleable

  3. Hard

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

Element that is relatively strong have strong force of attraction and difficult to break and are considered to be relatively hard.