1. . The cuprite ore of copper is:
(A) Cu₂S·Fe₂S₃
(B) Cu₂O
(C) CuO
(D) All three
2. . Iron reacts chemically with steam to form:
(A) FeO
(B) Fe₂O₃
(C) All three
(D) Fe₃O₄
3. . Iron reacts with concentrated sulphuric acid to liberate gas:
(A) CO₂
(B) No one
(C) SO₃
(D) SO₂
4. . Copper reacts with concentrated nitric acid to liberate gas:
(A) CO₂
(B) SO₂
(C) NO₂
(D) No one
5. . Aluminium reacts with dilute nitric acid to liberate gas:
(A) H₂
(B) SO₂
(C) NO₂
(D) No one
6. . The siderite ore of iron is:
(A) Fe₂O₃
(B) FeS₂
(C) All three
(D) FeCO₃
7. . The cryolite ore of aluminium is:
(A) Al₂O₃
(B) All three
(C) Al₂O₃·2H₂O
(D) Na₃AlF₆
8. . Thermite reaction is the reaction of metal oxide with:
(A) Cu
(B) Al
(C) Zn
(D) Fe
9. . Which metal gives blue colour with ammonia solution:
(A) Cu
(B) Al
(C) Zn
(D) Fe
10. . Which metal is liquid at room temperature:
(A) Cu
(B) Hg
(C) Zn
(D) Al
11. . In corrosion the chemical reaction is:
(A) Reduction
(B) Oxidation
(C) Decomposition
(D) Displacement
12. . Which one of the following causes corrosion of iron:
(A) Oxygen
(B) Hydrogen
(C) Moisture and oxygen
(D) Strong base
13. . Which one of the following metal does not corrode:
(A) Platinum
(B) Zinc
(C) Sodium
(D) Magnesium
14. . A process in which metal is protected from corrosion by dipping it in molten zinc is called:
(A) Tinning
(B) Cladding
(C) Electroplating
(D) Galvanization
15. . The bonding together of dissimilar metals by pressure is called:
(A) Cladding
(B) Calorizing
(C) Galvanization
(D) Chromizing
16. . The most important property of stainless steel is its:
(A) High resistance to corrosion
(B) Density
(C) Low strength
(D) Colour
17. . In bronze percentage of copper is:
(A) 60
(B) 70
(C) 80
(D) 90
18. . Nichrome is an alloy of nickel, chromium and:
(A) Zn
(B) Sn
(C) Fe
(D) Mn
19. . Which alloy is used to fill dental cavities:
(A) Brass
(B) Nichrome
(C) Duralumin
(D) Silver amalgam
20. . Which alloy has iron:
(A) Bronze
(B) Brass
(C) Stainless steel
(D) Solder