1. Which type of surface coating doesn’t use diluents?
a) Oil-based paints
b) Lacquers
c) Varnishes
d) Water-based paints
Explanation: Water-based paints doesn’t require diluents where as oil-based paints, lacquers, and varnishes uses naphtha’s and turpentine as diluents (thinner).
2. Agglomeration is a mode of drying in _________________
a) Water-based paints
b) Enamels
c) Oil-based paints
d) Lacquers
Explanation: Evaporation and agglomeration are modes of drying of ware-based paints. Oxidation and polymerization are modes of drying of oil-based paints and varnishes. Lacquers mode of drying is evaporation.
3. Which of the following is a colored pigment?
a) Zinc oxide
b) Lithopone
c) Lead chromate
d) Titanium dioxide
Explanation:White lead, lithopone, zinc oxide, titanium dioxide are all white pigments. Lead chromates, Prussian blue, and different iron oxides are colored pigments.
4. Which of the following pigment is an anti-corrosive pigment?
a) Prussian blue
b) Zinc chrome
c) Titanium dioxide
d) Carbon black
Explanation: Apart from prime pigments Ultramarine blue, Prussian blue, phthalocyanine blue, titanium dioxide, carbon black etc anti-corrosive pigments like zinc chrome and basic lead sulfates are developed.
5. What percentage of zinc oxide is present in a typical exterior white paint?
a) 15% ZnO
b) 50% ZnO
c) 25% ZnO
d) 10% ZnO
Explanation: A typical exterior white paint contains 15% TiO2, 25%ZnO, 50% white lead, and 10% pigment extender. Paint with this composition has self cleaning feature by a process called chalking process.
6. Temperature at which the reaction TiCl4 + O2 → TiO2 + 2Cl2 takes place is __________
a) 500°C
b) 1500°C
c) 1000°C
d) 2000°C
Explanation:Temperature at which the reaction TiCl4 + O2 → TiO2 + 2Cl2 takes place is 1500°C. Specially designed refractory lined furnaces are used. Chlorine is recovered for recycle.
7. Rutile grade titanium dioxide is produced in _____________
a) Travancore titanium products limited (TTP)
b) Kilburn chemicals limited
c) Kolmak chemicals limited
d) Kerala minerals and metals limited (KMML)
Explanation:Travancore titanium products limited (TTP), Kilburn chemicals limited, Kolmak chemicals limited produces titanium dioxide pigment using sulfate route whereas Kerala minerals and metals limited (KMML) produces rutile grade titaniium oxide.
8. Oils are used for dual purpose in surface coating formulation.
a) True
b) False
Explanation: The statement is true as oils are used as carriers for pigments and as formers of the protective films. Hence they serve a dual purpose in surface coating formulation.
9. Semi-drying oil is ____________
a) Linseed
b) Soya bean oil
c) Coconut oil
d) Castor oil
Explanation: Based on degree of unsaturation, oils are classified as drying oils and semi-drying oils. Examples of drying oils are linseed, soya bean, castor oil, Tung oil, and tall oil. Examples of semi-drying oils are coconut oil, tobacco seed etc.
10. . Resins are not used in _____________
a) Oil-based paints
b) Water based paints
c) Varnishes
d) Lacquers
Explanation: Oil based paints doesn’t use resins. Water based paints doesn’t use oils and depend on resins as film forming materials. Lacquers and varnishes use alkyd resins, phenolic etc.