3. Softness of silver can be converted into hardness by alloying it with small quantity of
4. The addition of antimony in tin-based alloys improves its
5. The melleability of a material is the property by virtue of which it can be rolled or hammered into thin sheets. Which of the following materials has the miximum malleability ?
6. The main purpose of galvanising iron sheets is to
7. The impure iron (pig iron) that is tapped out from blast furnace contains about __________ percent carbon.
8. Invar used in thermocouples is an alloy of nickel and
9. Nickel (56%) and molybdenum (17%) alloys are called
10. Lead pipes are not safe for carrying drinking water because water containing dissolved oxygen attacks lead thereby forming poisonous Pb (OH)2. Lead pipes are readily corroded by
11. Residual magnetism in steel for magnets is increased by the addition of
12. Presence of nickel in steel improves its
13. Cementite is
14. Acetylene gas holder is made of
15. Sulphur melting pit in the sulphuric acid plant is made of
16. The hardest material just prior to diamond in Mho's scale is
17. Percentage elongation of a material is a measure of its
18. Chlorination of benzene is done to produce benzene hexachloride (a pesticide) in a photochemical reactor lined with
19. Heavy duty bearings are usually made of
20. Dielectric strength of a material is
21. Which of the following stainless steels is non-magnetic ?
22. 18-4-1 high speed steel contains 18%, 4% and 1% respectively of
23. Aluminium as a material of construction suffers from the disadvantage of
24. Babbit metal used for bearings is a____base alloy.
25. 18/8 steel is a/an __________ stainless steel.