Free Plant Design and Economics MCQs with Answers

• A. Brittle
• B. Whitish in color
• C. Malleable
• D. Strong and hard

Explanation: White cast iron contains carbon mainly as cementite, making it very hard but brittle and difficult to machine or deform.

• A. Not resistant to corrosion
• B. Used as a cathodic material
• C. Not used as pigment (in its compound forms) for paints
• D. Used as a shock absorber (in mattress form) between the foundation and steel framework of
• E. skyscraper buildings

Explanation: Lead is highly corrosion-resistant and is used in sheet or mattress-like layers to absorb vibration and shock in heavy structures.

• A. Pig iron
• B. Wrought iron
• C. Low carbon steel
• D. Mild steel

Explanation: Pig iron is the blast-furnace product containing high carbon and impurities; it is remelted and cast into useful cast-iron shapes.

• A. Rupture strength and hot hardness
• B. Deformation resistance
• C. Impact strength and bonding strength
• D. Wear resistance

Explanation: Antimony strengthens tin-based alloys and makes them more resistant to plastic deformation under load.

• A. Increases in proportion to stress
• B. Decreases very quickly
• C. Increases very quickly
• D. Decreases in proportion to stress

Explanation: At the elastic limit, the material begins to yield, so a small further increase in stress produces a comparatively large increase in…

• A. Monel metal
• B. Gun metal
• C. Wood metal
• D. Babbitt metal

Explanation: Monel, a nickel-copper alloy, resists concentrated caustic soda and many other alkaline environments.

• A. Lead lined stainless steel
• B. Steel or cement-brick lined
• C. Cast iron
• D. Hard wood

Explanation: A sulphur melting pit is commonly constructed from steel with a cement-brick lining to withstand heat and protect the steel from the…

• A. Platinum & mercury
• B. Iron & mercury
• C. Iron & carbon
• D. None of these

Explanation: Iron and carbon form iron-carbon alloys such as steel and cast iron, with their properties controlled by carbon content.

• A. Malleability
• B. Ductility
• C. Thermal & electrical conductivity
• D. Tensile strength

Explanation: Copper is highly malleable and ductile and is an excellent conductor of heat and electricity.

• A. Aluminium
• B. Copper
• C. High carbon steel
• D. Nickel

Explanation: Aluminium is suitable for storing refined acetic acid because it develops a protective oxide film and resists attack by the acid under…

• A. Fish plates
• B. Channels
• C. Die block
• D. Drop forging

Explanation: Mild steel is widely used for structural sections such as channels because it is strong, ductile, weldable and economical.

• A. Carbon content
• B. Manufacturing process
• C. Hardness
• D. Tensile strength

Explanation: Cast irons are commonly designated by their tensile strength because their carbon content and manufacturing route vary widely among…

• A. Concrete
• B. Cast iron
• C. Nickel
• D. Steel with top section nickel clad or stainless steel

Explanation: A soap kettle handles hot, corrosive alkaline liquor, so its body is commonly steel with the upper or most exposed section nickel-clad or…

• A. Corrosion resistance
• B. Cutting ability
• C. Wear resistance
• D. All A., B. and C.

Explanation: Nickel improves the corrosion resistance of steel by promoting a more stable and protective alloy surface.

• A. Caustic soda
• B. All A., B. and C.
• C. Hypochlorous acid
• D. Chlorinated brine

Explanation: Rubber linings provide resistance to caustic soda, chlorinated brine and hypochlorous acid, allowing the pump casing to handle these…

• A. Fireclay bricks
• B. Calcium carbide
• C. Silicon carbide
• D. High alumina bricks

Explanation: Silicon carbide is used for ceramic recuperators because it withstands high temperatures, thermal shock and oxidation while retaining good…

• A. For producing zinc base die casting alloys
• B. In its oxide form as pigments
• C. As anode for corrosion prevention in boiler
• D. As an alloying element in various bronzes

Explanation: Zinc is used in die-casting alloys, zinc-oxide pigments and sacrificial anodes for boiler corrosion protection.

• A. Alum
• B. Saturated brine
• C. Sulphuric acid
• D. Ferrous sulphate

Explanation: Concrete tanks are suitable for saturated brine because the salt solution is not strongly acidic.

• A. Resistance to brittleness
• B. Ductility
• C. Shock resistance
• D. Compressive strength

Explanation: Cast iron withstands very high compressive loads because its graphite-rich structure resists squeezing.

• A. Duralumin
• B. Hastelloy
• C. Nimonic alloys
• D. Inconel

Explanation: Duralumin is an aluminium-copper alloy, not a nickel-chromium alloy. Inconel, Hastelloy and Nimonic alloys are nickel-based alloys…