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 reactivity series and electrochemistry reactivity series and displacement reactions chemical properties of metals chemical properties of metals and non metals

Iron can displace ________ from its solution.

  1. $Cu$
  2. $Al$
  3. $Zn$
  4. $Mg$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Iron can displace $Cu$ from its solution

Reactivity series: Highest $\longrightarrow$ Lowest
$K>Na>Ca>Mg>Al>Zn>Fe>Sn>Pb>Cu>Ag>Au$
Highly reactive elements can displace less reactive elements from their solution.

Multiple choice chemistry reactivity series and electrochemistry reactivity series and displacement reactions chemical properties of metals chemical properties of metals and non metals

Copper can be displaced from aqueous solution of copper sulphate by adding:

  1. $Ag$
  2. $Au$
  3. $Pt$
  4. $Fe$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$Fe(s)+CuSO _4(aq)\longrightarrow Cu(s)+FeSO _4(aq)$

Metals like $Zn, Pb, Fe$ and $Al$, displace $Cu$ from copper salt solution.
Reactivity series of metals: $K>Na>Ca>Mg>Al>Zn>Fe>Sn>Pb>Cu>Ag>Au$
So, $K$ is most reactive and $Au$ is least reactive. Metals which are more reactive than that element can displace that element from its salt solution.

Multiple choice chemistry reactivity series and electrochemistry reactivity series and displacement reactions chemical properties of metals chemical properties of metals and non metals

Mark the incorrect statement.

  1. Reactive metals can displace less reactive metals from their compounds in solution

  2. All metals are not equally reactive

  3. Both A and B

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

Reactive metals can displace less reactive metals from their compounds in solution or molten form. All metals are not equally reactive. Their reactivity is different for different metals.

Multiple choice chemistry reactivity series and electrochemistry reactivity series and displacement reactions chemical properties of metals chemical properties of metals and non metals

Statement 1: Zinc metal will reduce $Cu^{2+}$ in solution.

Statement 2: Zinc is a more active metal than copper.

  1. <p>Both Statement 1 and Statement 2 are correct and Statement 2 is the correct explanation of Statement 1.</p>

  2. <p>Both Statement 1 and Statement 2 are correct but Statement 2 is the correct explanation of Statement 1.</p>

  3. <p>Statement 1 is correct but Statement 2 is not correct.</p>

  4. <p>Statement 1 is not correct but Statement 2 is correct.</p>

  5. Both the Statement 1 and Statement 2 are not correct.

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In the activity series of metal $Zn$ is above the $Cu$ metal. So it can easily reduce $Cu^{2+}$ in the solution.

Multiple choice chemistry reactivity series and electrochemistry reactivity series and displacement reactions chemical properties of metals chemical properties of metals and non metals

Food cans are coated with tin and not with zinc because:

  1. zinc is costlier than tin

  2. zinc has a higher melting point than tin

  3. zinc is more reactive than tin

  4. zinc is less reactive than tin
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Food cans are coated with tin and not with zinc because zinc is above the tin in reactivity series means more reactive than tin and can react with food elements preserved in it.  

Multiple choice evs let's play with water law of constant proportion - i law of constant proportion law of definite proportions

A solution of copper oxide was prepared by heating, igniting and precipitation. Which of the following method will give higher ratio of copper oxide?

  1. Heating

  2. Precipitation

  3. Ignition

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

In a compound the ratio of the atoms or element by mass remains always same irrespective of the source of compound. This means a certain compound always formed by the combination of atoms in same ratio by mass. Hence, copper oxide made from any method will always give the same ratio of copper oxide.

Multiple choice evs let's play with water law of constant proportion - i law of constant proportion law of definite proportions

The percentage of copper and oxygen in a sample of CuO obtained from different methods were found to be same. This proves the law of :

  1. Constant proportion

  2. Multiple proportion

  3. Reciprocal proportion

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

The percentage of copper and oxygen in a sample of CuO obtained from different methods were found to be same. This proves the law of Constant proportion as the ratio of Cu:O remains constant

Multiple choice evs let's play with water law of constant proportion - i law of constant proportion law of definite proportions

The percentage of copper and oxygen in samples of CuO obtained by different methods were found to be the same. This illustrates the law of:

  1. Constant proportion

  2. Conservation of mass

  3. Multiple proportion

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

In chemistry, the law of definite proportions, sometimes called Proust's law or the law of definite composition, states that a chemical compound always contains exactly the same proportion of elements by mass and this law further says that, in any particular chemical compound, all samples of that compound will be made up of the same elements in the same proportion or ratio. For example, any water molecule is always made up of two hydrogen atoms and one oxygen atom in a ratio.

Multiple choice biology movement in and out of the cell transport of molecules osmosis and plasmolysis plant water relation

Mineral absorption is mostly

  1. Physical process

  2. Chemical process

  3. Active process

  4. Passive process
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Mineral absorption takes place in two phases: active absorption and passive absorption. It mostly occurs using active absorption phase because it is a fast process of mineral absorption, utilise energy and unidirectional. It is a biochemical process that occurs against the concentration gradient with the help of carriers and pumps.
So the correct answer is 'Active process'.
Multiple choice chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

Blister copper obtained during extraction from cuprous oxide is called so because:

  1. it has blister like eruptions due to evolution of gas

  2. it has a shining surface like blister

  3. it is the most impure form of copper

  4. its surface is uneven due to different thickness at different place
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The various reaction involved in extraction of copper from cuprous oxide are:
$2FeS+3O _2 \rightarrow 2FeO+2SO _2$
$FeO+SiO _2 \rightarrow FeSiO _3$
$2Cu _2S+3O _2 \rightarrow 2Cu _2O+2SO _2$
$2Cu _2O+Cu _2S \rightarrow 6Cu+SO _2$
The solidified copper obtained has blistered appearance due to the evolution of $SO _2$ and so it is called blister copper.

Multiple choice chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

Why is partial roasting of sulphide ore done in metallurgy of copper?

  1. Auto-reduction of $CuO$ formed is carried out by remaining $CuS$ in the reaction.
  2. $Cu$ is separated out by partial reduction due to sedimentation.
  3. Due to difference in gravity $CuO$ and $CuS$ are separated.

  4. Complete roasting cannot be done in one step hence partial roasting is done.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Partial reduction of Sulphide ores gives copper oxide which further reacts with copper sulphide to show an auto reduction.

$2CuS+3O _2\longrightarrow 2CuO+2SO _2$
$2CuO+CuS\overset {Autoreduction}{\longrightarrow}3Cu+SO _2$

Multiple choice chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

Blister copper is:

  1. impure copper

  2. obtained in self-reduction process during bessemerisation

  3. both are correct

  4. none is correct
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Blister copper is a form of a impure copper which is obtained in self reduction process during bessemerization.

Reactions take place in blast furnace-
$2Cu _2O+Cu _2S\longrightarrow 6Cu+SO _2$
The molten metal is cooled in sand moulds $SO _2$ escapes. The impure copper metal is known as "Blister copper" and is about $98\%$ pure.

Multiple choice chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

Mark the incorrect statement.

  1. Copper is extracted by smelting in a reverberatory furnace.

  2. Zinc is extracted by reduction of oxide with aluminum.

  3. Aluminium is extracted by electrolysis of its oxide.

  4. Iron is extracted by reduction of its oxide in blast furnace.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
It is not profitable method for extraction of Zinc. Zinc is extracted by distillation and by electrolytic refining. So, it is not extracted by reduction of oxide with Aluminium.
Multiple choice chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

Which of the following metals is extracted using a silica lined convertor?

  1. $Mg$
  2. $Al$
  3. $Cu$
  4. $Zn$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

During the extraction of copper from cuprous oxide $(copper[I]oxide)$ the ore is heated in a reverberatory furnace after mixing with silica. In the furnace, iron oxide, slag of iron silicate and copper is produced in the form of copper matte. This contains $Cu _2S$ and $FeS$.

$FeO+SiO _2\longrightarrow \underbrace {FeSiO _3} _{(slag)}$
Copper matte is then charged into silica lined converter. Some silica is also added and hot air blast is blown to convert the remaining $FeS _2, FeO$ and $Cu _2S/Cu _2O$ to metallic copper.

Multiple choice chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

Zinc is refined by :

  1. Liquation (or) distillation under reduced pressure

  2. Electrolytic method or polling

  3. Liquation or electrolytic method

  4. Distillation under reduced pressure or electrolytic method
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Zinc is refined by distillation under reduced pressure or electrolytic method. Distillation is very useful for low boiling metals like zinc and mercury. The impure metal is evaporated to obtain the pure metal as distillate.