Free Plant Design and Economics MCQs with Answers

• A. Nuts
• B. Bolts
• C. Studs
• D. Chisels

Explanation: Steel with about 0.4% carbon is medium-carbon steel and is suitable for nuts, bolts, and studs after suitable processing.

• A. Alkaline solutions
• B. Milk and fruit juices
• C. Dilute H2SO4 at room temperature
• D. Brine

Explanation: Glass and Pyrex resist many acids, including dilute sulphuric acid, but strong alkaline solutions attack glass and can damage the pump.

• A. Molybdenum and nickel
• B. Nickel and copper
• C. Molybdenum and aluminium
• D. Molybdenum and zinc

Explanation: Monel is primarily a nickel-copper alloy, with small amounts of iron, manganese, and other elements.

• A. Stainless steel
• B. Wrought iron
• C. Copper
• D. Tin

Explanation: Tin melts at about 232°C, far below copper, wrought iron, and stainless steel, whose melting temperatures are roughly above 1,000°C.

• A. Beer
• B. Aqueous ammonia
• C. H2SO4 (95%)
• D. Phosphoric acid (95%)

Explanation: Brass is comparatively suitable for beer service, whereas ammonia attacks copper alloys and concentrated sulphuric or phosphoric acids are…

• A. Easily machinable
• B. Highly wear resistant
• C. Soft on surface
• D. None of these

Explanation: Rapid cooling of chilled iron forms a hard white-iron layer rich in carbides at the casting surface.

• A. Fatigue
• B. Endurance
• C. Creep
• D. None of these

Explanation: Creep is the gradual, time-dependent deformation of a material under sustained stress, especially at elevated temperature.

• A. Grey iron
• B. Pig iron
• C. Bessemer iron
• D. Wrought iron

Explanation: Wrought iron is the purest of these traditional commercial iron forms, containing very little carbon and much less impurity than pig iron…

• A. Iron
• B. Silver
• C. Tin
• D. Copper

Explanation: Iron readily reacts with oxygen and moisture to form rust, so it is more prone to atmospheric corrosion than silver, tin, or copper.

• A. Ductility
• B. Fluidity & castability
• C. Strength
• D. Malleability

Explanation: Cast iron contains more carbon and melts at a lower temperature with good fluidity, allowing it to fill intricate moulds easily.

• A. Lead
• B. Cadmium
• C. Aluminium
• D. Magnesium

Explanation: Aluminium, lead, and cadmium are used as protective coating metals in suitable applications.

• A. Steel
• B. Cast iron
• C. Asbestos cement
• D. Reinforced cement concrete

Explanation: A cast-iron detachable joint, such as a mechanical coupling arrangement, is commonly used to join steel pipes where dismantling is…

• A. Bismuth
• B. Both B. and C.
• C. Antimony
• D. Arsenic

Explanation: Arsenic and antimony dissolve in copper and strongly scatter conduction electrons, causing a large fall in electrical conductivity even at…

• A. Magnesium & tin
• B. Ferrous material
• C. Copper & zinc
• D. Lead & tin

Explanation: Muntz metal is a copper-zinc alloy containing approximately 60% copper and 40% zinc.

• A. Copper and tin
• B. Copper and nickel
• C. Lead and tin
• D. Molybdenum and nickel

Explanation: Hastelloy refers to corrosion-resistant nickel-based alloys, many grades of which contain substantial molybdenum along with nickel.

• A. 0.1-2
• B. 4-6
• C. 2-4
• D. 0.001-0.01

Explanation: Steel is an iron-carbon alloy containing roughly 0.1 to 2% carbon; above about 2% carbon, the alloy is generally classified as cast iron.

• A. Nickel
• B. Steel
• C. Cast iron
• D. Karbate

Explanation: Nickel has excellent resistance to concentrated caustic soda, including hot NaOH solutions, so it is suitable for the evaporator and…

• A. Pig iron
• B. Wrought iron
• C. None of these
• D. High carbon steel

Explanation: Iron containing up to about 2% carbon is normally called steel, but that option is missing.

• A. High alloy
• B. Medium carbon
• C. High carbon
• D. Low carbon

Explanation: Mild steel is low-carbon steel, usually containing about 0.05 to 0.25% carbon, which gives it good ductility and weldability.

• A. Toughness
• B. Resilience
• C. Malleability
• D. Ductility

Explanation: Toughness is the energy a material absorbs before fracturing, represented by the total area under its stress-strain curve.