Q1. Gangue mainly consists of:
Q2. Brass is an alloy of:
Q3. Metals obtained after extraction are generally:
Q4. Rusting of iron can be prevented by:
Q5. Metals like iron and zinc are:
Q6. These metals are usually found as:
Q7. Galvanisation involves coating iron with:
Q8. Copper can be extracted from Cu₂S by:
Q9. The removal of gangue from ore is known as:
Q10. Rusting of iron requires:
Q11. Solder is an alloy of:
Q12. Mercuric oxide decomposes on heating to form:
Q13. Highly reactive metals are obtained by:
Q14. 22-carat gold means:
Q15. Copper develops a green coating of:
Q16. Obtaining metals from their compounds is a:
Q17. An alloy containing mercury is called:
Q18. In electrolytic refining, impure metal is made the:
Q19. Silver turns black due to formation of:
Q20. The impurities present in an ore are called:
Q21. Pure iron is not used widely because it is:
Q22. Calcination of ZnCO₃ produces:
Q23. Separation techniques depend on the difference in:
Q24. Sodium is obtained by electrolysis of:
Q25. Metals low in the activity series are:
Q26. Zinc oxide is reduced to zinc using:
Q27. In electrolytic refining, pure metal is deposited on:
Q28. It is easier to extract metals from their:
Q29. Heating carbonate ores in limited air is called:
Q30. Stainless steel is an alloy of iron with:
Q31. Bronze is an alloy of:
Q32. Metals at the top of activity series cannot be reduced by:
Q33. An alloy is a:
Q34. The brown flaky substance formed on iron is:
Q35. Aluminium can act as a reducing agent because it is:
Q36. Solder is used for:
Q37. Thermit reaction is:
Q38. The rust resistance of the iron pillar near Qutub Minar is due to formation of:
Q39. Insoluble impurities settle at the bottom as:
Q40. The reaction between Fe₂O₃ and aluminium is called:
Q41. During electrolysis of molten NaCl, chlorine is liberated at:
Q42. Cinnabar is an ore of:
Q43. Oxides of low reactivity metals can be reduced by:
Q44. Heating sulphide ores in excess air is called:
Q45. During electrolysis of molten NaCl, sodium is deposited at:
Q46. The most widely used refining method is:
Q47. Roasting of ZnS produces:
Q48. Thermit reaction is used for:
Q49. Alloys generally have ______ conductivity than pure metals:
Q50. On heating cinnabar in air, it first forms: