Unit Operations and Process Equipment MCQs 2026

Tray dryer removes moisture by

1. A electrolysis ✓
2. B distillation reflux only internal ✓
3. C centrifugal separation only ✓
4. D hot air passing over solid material on trays ✓

Crystallization yield improves by

1. A increasing impurities always ✓
2. B controlled cooling or evaporation to supersaturation ✓
3. C random agitation only without supersaturation ✓
4. D eliminating nucleation always ✓

Fluidized bed condition occurs when

1. A particles are glued ✓
2. B only vacuum ✓
3. C only laminar pipe flow ✓
4. D gas velocity supports particle weight with drag ✓

Cyclone separator removes particles primarily by

1. A diffusion only ✓
2. B centrifugal force in swirling flow ✓
3. C osmosis ✓
4. D electroplating ✓

Filtration rate often decreases with time in constant-pressure filtration because

1. A viscosity becomes zero ✓
2. B filter area doubles ✓
3. C cake resistance increases ✓
4. D pressure rises ✓

Agitator power number depends on

1. A impeller geometry and Reynolds number in vessel ✓
2. B only pipe length ✓
3. C only stack height ✓
4. D only moon phase ✓

Spray dryer produces powder by

1. A evaporating droplets in hot gas ✓
2. B compressing gas isothermally ✓
3. C freezing only without mass transfer ✓
4. D gravity settling only ✓

Sedimentation clarifier separates by

1. A magnetic field only ✓
2. B gravity settling of particles ✓
3. C chemical reaction only ✓
4. D adsorption in zeolite only ✓

Membrane ultrafiltration separates by

1. A only boiling point difference ✓
2. B molecular size through porous membrane ✓
3. C only magnetic susceptibility ✓
4. D only photon energy ✓

Ball mill is used for

1. A distillation ✓
2. B ion exchange ✓
3. C size reduction by impact and attrition ✓
4. D electrorefining only ✓