This set of Basic Civil Engineering Multiple Choice Questions & Answers (MCQs) focuses on “Painting”.
1. In a white wash, after how many hours is dissolved gum added to solution?
a) 24 hours
b) 12 hours
c) 6 hours
d) 1 hour
Explanation: White wash is prepared from fat lime. Fat lime is dissolved in a big drum and it is stirred well. Then, after 24 hours dissolved gum is added to the drum.
2._________ are cheaper varieties of paint.
a) Colour wash
Explanation: Distempers have chalk as base, water as carrier and emulsifying agents like glue or casein. To impart colour, pigments are added.
3. A paint normally consists of _________ components.
Explanation: The six components that comprise paint are base, vehicle, solvent, pigment, filler and drier. Out of these, the base, vehicle and solvent are the important ones.
4. _________ paint gets deteriorated when exposed to sun.
Explanation: Bituminous paint is applied on to iron works under water. It is made by dissolving asphalt or bitumen in oil or petroleum. It has a characteristic black colour.
5. The appearance of glossy patches on the painted surface is called:
Explanation: Flashing is a defect developed on painted surface. It is identified as glossy patches on the surface. It is caused due to poor quality of paint or of workmanship.
6. Which of the below is a pigment imparting brown colour?
a) Raw sienna
c) Burnt sienna
Explanation: Raw sienna imparts yellow colour to paint. To get black colour, soot is added. Blue colour can be obtained by adding ultramarine pigment.
7. The component filler in paint does the function of:
a) Absorbing oxygen
b) Reducing cost
d) Smooth spreading
Explanation: Fillers are added to reduce the cost of paint. Too much addition of it may weakenthe paint. Commonly used ones are alumina, magnesia, barite, charcoal, etc.
8. Saponification is a defect on painted surface and it is identified by the appearance of:
b) Dull patches
d) Soapy patches
Explanation: Saponification leads to the appearance of soapy patches. It occurs due to chemical reaction of alkalis. To avoid this, surface must be cleaned and paint should be kept away from strong alkalis.
9. Which of the below is not an example of base?
a) White lead
c) Zinc oxide
d) Red lead
Explanation: Cobalt is used as a drier. It absorbs oxygen from surroundings and hardens the paints. White lead, zinc oxide and red lead are all examples of base. They have binding properties and form opaque coat.
10. Which paint contains polystyrene as base?
a) Synthetic rubber
Explanation: Emulsion paint contains polystyrene and polyvinyl acetate as base. They are durable and retain their colour for long. They dry within 15 minutes and hard dry within 2 hours.
11. Which defect occurs if paint is applied excessively thick?
Explanation: Grinning occurs when under coat and final coat are of different colours. The opacity is insufficient and background colour is visible. Running occurs if surface is too smooth; paint run off from such parts. Flaking occurs due to poor adhesion, leading to peeling off of paint.
Sanfoundry Global Education & Learning Series – Basic Civil Engineering.
To practice all areas of Basic Civil Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.