1. . Following are common non-ferrous metals:
(A) Copper, zinc and lead
(B) Brass, nickel and bronze
(C) Aluminum, magnesium and cobalt
(D) All these
2. . Zinc has tensile strength of 190 to:
(A) 250 kg/cm²
(B) 350 kg/cm²
(C) 550 kg/cm²
(D) 750 kg/cm²
3. . Steps involved in getting metallic copper from copper ore are:
(A) Concentration and refining
(B) Roasting and smelting
(C) Converting and refining
(D) All of these
4. . The most important ore of aluminium is:
(A) Cryolite
(B) Bauxite
(C) Corundum
(D) None of these
5. . Aluminium is used as a heat exchanger due to its property of:
(A) Low density
(B) High thermal conductivity
(C) High electrical conductivity
(D) All of these
6. . In steel making process aluminium is used as:
(A) Deoxidiser
(B) Oxidiser
(C) Recarburizer
(D) Reducing agent
7. . The melting point of aluminium is:
(A) 836°C
(B) 780°C
(C) 659°C
(D) 930°C
8. . Aluminium does not chemically react with:
(A) Nitric acid
(B) Sulphuric acid
(C) Hydrochloric acid
(D) All of these
9. . Corundum is an ore of:
(A) Zinc
(B) Aluminium
(C) Chromium
(D) Copper
10. . The slag is:
(A) Molten metal
(B) Slag
(C) Flux
(D) Complex of impurities
11. . The blister copper is obtained by:
(A) Roasting
(B) Poling
(C) Refining
(D) Bessemer
12. . Alloy of copper and zinc is called:
(A) Alloy of zinc
(B) Gunmetal
(C) Brass
(D) All of these
13. . Alloy of copper and tin is called:
(A) Bronze
(B) Gunmetal
(C) Alpha brass
(D) None of these
14. . The melting temperature of nickel is:
(A) 1055°C
(B) 1255°C
(C) 1455°C
(D) 1655°C