Free Plant Design and Economics MCQs with Answers

• A. 1.5 to 2
• B. 0.4 to 0.7
• C. 0.8 to 1.5
• D. 0.1 to 0.35

Explanation: Low-carbon steel generally contains about 0.05 to 0.30% carbon, so 0.1 to 0.35% is the closest listed range.

• A. Monel metal
• B. Hastelloy
• C. German silver
• D. Inconel

Explanation: Monel is a nickel-copper alloy, commonly containing roughly two-thirds nickel and one-third copper, with excellent corrosion resistance.

• A. Nickel
• B. Copper
• C. Stainless steel
• D. Brass

Explanation: Copper tubes were traditionally used in multiple-effect evaporators for sugar-cane juice because copper has good thermal conductivity and…

• A. Nickel
• B. Aluminium
• C. Rubber
• D. Glass

Explanation: Sulphuric-acid pickling tanks are commonly protected with rubber linings, which isolate the structural tank metal from the acid.

• A. Hardness & brittleness increases
• B. Ductility decreases
• C. Neither A. nor B.
• D. Both A. and B.

Explanation: A higher carbide-to-graphite ratio produces a harder, more brittle cast iron because carbides are hard and brittle while graphite…

• A. Mica
• B. Glass
• C. Brass
• D. Cast iron

Explanation: Glass is amorphous because its atoms lack the long-range, repeating crystal structure found in crystalline solids.

• A. Plain carbon steel
• B. Stainless steel
• C. Rubber or durmet-20 lined
• D. Lead

Explanation: Ammonium chloride solutions are strongly corrosive to many ordinary metals, so equipment is protected with rubber or Durmet-20 linings.

• A. Precipitation
• B. Fusion
• C. Agglomeration
• D. Sintering

Explanation: Sintering is the controlled heating of compacted metal powder below its melting point, allowing particles to bond and gain strength.

• A. Cast iron
• B. Stainless steel
• C. Karbate
• D. Lead lined steel

Explanation: Cast iron is used for the Solvay carbonating tower because it withstands the alkaline ammoniacal brine and carbon dioxide environment at…

• A. Graphite
• B. Diamond
• C. Carborundum
• D. Pumice stone

Explanation: Diamond is the hardest naturally occurring material because its carbon atoms form a very strong three-dimensional covalent network.

• A. Tempering
• B. Annealing
• C. Normalising
• D. None of these

Explanation: Normalising heats steel above its critical range and then cools it in air, refining the grain structure and reducing the effects of…

• A. Stainless steel
• B. Titanium
• C. Aluminium
• D. Lead

Explanation: Lead has a density of about 11.3 g/cm³, higher than the listed metals, and melts at only about 327°C.

• A. Copper & iron
• B. Copper & copper-nickel alloys
• C. Iron & nickel
• D. Tin & nickel

Explanation: Platinum thermocouples use copper and copper-nickel alloy compensation or lead wires because these combinations reproduce the…

• A. Titanium
• B. Aluminium
• C. Magnesium
• D. Tin

Explanation: Magnesium is the lightest of the commonly used engineering metals, with a density of about 1.7 g/cm³.

• A. Duriron
• B. Karbate
• C. Aluminium
• D. Nickel

Explanation: Nickel has excellent resistance to alkaline corrosion, particularly in caustic soda service.

• A. Cast iron
• B. Mild steel
• C. Stainless steel
• D. Galvanised iron

Explanation: Traditional plate-and-frame filter presses use cast-iron plates and frames because cast iron is rigid, strong, and economical.

• A. Monel metal
• B. Solder
• C. Duralumin
• D. Bronze

Explanation: Monel is a copper-nickel alloy containing a high proportion of nickel, commonly about 60–70% nickel.

• A. Caustic soda solution
• B. None of these
• C. Sulphuric acid (10%)
• D. Phosphoric acid

Explanation: Platinum is highly resistant to these dilute acids, while silver is not significantly attacked by 10% sulphuric acid under ordinary…

• A. Soft solder
• B. Casting for dental work
• C. Storage tank for storing brine and caustic soda
• D. Fusible safety plug for pressure cooker

Explanation: Wood's metal is a low-melting fusible alloy used in soft soldering, dental casting, and safety plugs.

• A. Inconel
• B. Monel
• C. Aluminium bronzes
• D. Brass

Explanation: An alloy containing approximately 76% nickel and 15% chromium corresponds to Inconel, a nickel-chromium alloy valued for high-temperature…