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 polyhalogen compounds haloalkanes and haloarenes chemistry

Which of the following is used for metal cleaning and finishing?

  1. $CHCl _{3}$
  2. $CHI _{3}$
  3. $CH _{2}Cl _{2}$
  4. $C _{6}H _{6}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Chloroform is used as solvent and as anaesthetic.
$CHI _3$ is used as antiseptic.
$CH _2Cl _2$ is used for metal cleaning and finishing.
$C _6H _6$ is used for printing and lithography, paint, rubber, dry cleaning, adhesives and coatings, detergents.

Multiple choice chemistry adsorption and colloids applications of colloids colloids around us the colloidal state

Tanning of leather is the :

  1. colouring of leather by chemicals

  2. drying process to make the leather hard

  3. polishing of leather to make it look attractive

  4. coagulative hardening of the leather by chemicals
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Tanning is the process that converts the protein of the raw hide or skin into a stable material which will not putrefy and is suitable for a wide variety of end applications. The principal difference between raw hides and tanned hides is that raw hides dry out to form a hard inflexible material that can putrefy when re-wetted (wetted back), while tanned material dries out to a flexible form that does not become putrid when wetted back. A large number of different tanning methods and materials can be used. The choice is ultimately dependent on the end application of the leather. The most commonly used tanning material is chromium, which leaves the leather, once tanned, a pale blue colour (due to the chromium), this product is commonly called wet blue.

Multiple choice physics units and measurement: error analysis accuracy of measurement accuracy and precision accuracy, precision and uncertainty in measurement

Why are shields made of iron usually provided around precision instruments?

  1. For protection against the effect of moisture in the air

  2. For guiding the instruments against unauthorised handling

  3. For protection against the effect of external magnetic fields

  4. For absorbing heat generated during the functioning of the instruments
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

 Metals like iron can be used to shield the instruments from external magnetic fields because magnetic fields cannot penetrate metallic surfaces.

Multiple choice physics electric current and its effects heating effect of electric current- uses applications of heating effect of electric current coil and fuse

Mark the correct reason/s why nichrome is used for making heating element of electrical appliances. 

  1. Nichrome does not oxidize

  2. Nichrome doesn't burn easily at high temperatures as it has higher melting and boiling point than metals

  3. Nichrome has higher resisistivity and consequently a higher resistance

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

Nichrome is used for making heating element of electrical appliances. Because nichrome does not oxidize and burn easily at high temperature i.e.it has higher melting and boiling point than metals. Thus it does not melt even when a large amount of heat is produced due to passage of current. Moreover, It has higher resisistivity and consequently a higher resistance.Therefore, it will resist the flow of charges more, and lead to development of heat faster.

Multiple choice physics electric current and its effects heating effect of electric current- uses applications of heating effect of electric current coil and fuse

Mark the correct reason why tungsten is used for making filament of electric lamp.

  1. Tungesten oxidises easily

  2. It has low boiling point

  3. It has high melting point

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

Tungsten is used in electric bulb because it has high melting point and it does not oxidize. Thus tungsten filament does not melt even when a large amount of heat is produced due to passage of current through the filament (via heating effect of current).

Multiple choice physics properties of material substances elastic behaviour of solids elastic and plastic substances properties of substances

A thin metal sheet is being bent by or pounded in to a new shape. The process of being elastic to plastic behaviour is known as 

  1. Yield

  2. Creep

  3. Welding

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

The yield point is the point on a stressstrain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Yielding means the start of breaking of fibers.

The correct option is option(a)

Multiple choice applications of adsorption adsorption adsorption and colloids surface chemistry chemistry

What is the role of adsorption in froth floatation process used especially for concentration of sulphide ores?

  1. Shape selective catalysts

  2. Adsorption of pine oil on sulphide ore particles

  3. Adsorption of pine oil on impurities

  4. Production of heat in the process of exothermic reaction
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • In Froth floatation process a low-grade sulphide ore is concentrated by separating it from silica and other earthy matter by this method using pine oil and frothing agent.
  • Pine oil is adsorbed on sulphide ore particles so as to facilitate the further process.
Multiple choice chemistry combustion structure of flame flame combustion, fuels and flame

Artificial rubies and sapphires can be made by heating alumina in ?

  1. An oxy-hydrogen flame

  2. An oxy-acetylene flame

  3. Burning methane

  4. An electric furnace
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Artificial ruby and sapphires are manufactured from alumina to which 1.5% of magnetic iron oxide and 0.5% of titanium oxide has been added, the mixture is fused and crystallised in an oxy-hydrogen flame. It is a reducing flame.

Multiple choice chemistry phenomena around us changes and its classification types of changes classification of changes

Iron pipes coated with zinc do not get rusted easily.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

It is true.

Coating iron with zinc is known as galvanizing. Iron metals get rusted when in contact with oxygen and moisture (air).
If coated with zinc, no interaction between oxygen and iron is there and hence the pipe does not get rusted easily.

Multiple choice chemistry phenomena around us comparison between physical and chemical changes introduction to physical and chemical changes change around us

Which of the following represents a chemical change?

  1. Rusting of iron.

  2. Magnesium burns in air leaving behind a powdery ash.

  3. Explosion of a firework.

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

All of the following represents a chemical change.

Rusting of iron.
Magnesium burns in air leaving behind a powdery ash.
Explosion of a firework.

Multiple choice physics heat and temperature anomalous expansion of water thermal expansion in solids, liquids and gases thermal expansion

why Loops are joined with the metal pipe line?

  1. capacity

  2. temperature

  3. pressure

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

Metals has the capacity to expand or contract due to temperature change. Metals pipe also expand in summer and contract in winter, such changes can cause deformities, inorder to avoid this, loops are joined with the metal pipe.

Multiple choice physics heat and temperature anomalous expansion of water thermal expansion in solids, liquids and gases thermal expansion

If a bimetallic strip is heated, it will

  1. Bend towards the metal with lower thermal expansion coefficient.

  2. Bend towards the metal with higher thermal expansion coefficient.

  3. Twist itself into helix.

  4. Have no bending.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Answer is A

A bimetallic strip consists of two metal strips fastened together. Metals are chosen that expand at different rates when the strips get hot. When one strip gets longer than the other, the combination has to bend. These strips are often used in thermostats in houses to control the house temperature. When the strip is cold, it bends one way, and as it gets hotter it bends the other way.

Multiple choice physics heat and temperature anomalous expansion of water thermal expansion in solids, liquids and gases thermal expansion

Iron or steel is used in reinforcement in concrete because

  1. Concrete has high coefficient of expansion than iron or steel

  2. Concrete has low coefficient of expansion than iron or steel

  3. Both have nearly equal coefficient of expansions

  4. Iron or steel is a good conductor of heat
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The properties of thermal expansion for both steel and concrete are approximately the same as both have nearly equal coefficient of expansion . This along with excellent bendability property makes steel the best material as reinforcement in concrete structures.