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CBSE CLASS X

One marks each

Q. 1. What is the basis of Mendeleev’s periodic law?

Q. 2. How many elements are there in a third period?

Q. 3. Sodium and potassium show similar reactivity towards water. What property do these elements possess in common?

Q. 4. Which of the elements F, Cl, Br, I is most reactive?

Q. 5. What are electropositive elements?

Q. 6. Name the bond formed in C₂H₄.

Q. 7. Why the melting point of metals is high?

Q. 8. Why the noble gases are stable.

Q. 9. Why does CCl₄ not conduct electricity?

Q. 10. Give an example of a molecule with double and triple bond.

Q. 11. NaCl is soluble in water but CCl₄ is not why?

Q. 12. What happens when lime water reacts with CO2? Write the complete reaction.

Q. 13. Give an example of redox reaction.

Q. 14. What happens when baking soda is heated strongly?

Q. 15. Is copper more reactive than iron? Give reaction in support of your answer.

Q. 16. Name one strong acid and strong base.

Q. 17. Why acetic acid is a weak acid?

Q. 18. Name the acid used in lead storage batteries.

Q. 19. What is the nature of the solution of NaCl in water?

Q. 20. Name the gas whose aqeous solution is basic.

Q. 21. What happens when hydrochloric acid reacts with caustic soda?

Q. 22. What happens when hydrochloric acid reacts with calcium carbonate?

Q. 23. Sulphides ores are generally concentrated by which method.

Q. 24. What is the nature of oxides of metals?

Q. 25. Define minerals and ores.

Q. 26. What is the most common property of metals lying at the bottom of the reactivity series.

Q. 27. What happens when CO₂ gas passed into water saturated with ammonia.

Q. 28. Define galvanization.

Q. 29. Name the oxide ore of aluminium.

Q. 30. Which two major constituents of duralium?

Q. 31. What is aqua regia. What is the property of this liquid.

Q. 32. Name the constituents of Brass and Bronze. What is their use?

Q. 33. What are the two things necessary for rusting?

Q. 34. Give the molecular formula of washing soda.

Q. 35. What is the general formula of alcohols ?

Q. 36. What is fermentation ?

Q. 37. Write the reaction of hydration of ethene.

Q. 38. Write the equation for the combustion of ethanol.

Q. 39. What is obtained when ethanol reacts with sodium metal?

Q. 40. What is esterification?

Q. 41. Write the chemical equation of oxidation of methanol to methanal.

Q. 42. Write the equation showing reaction between acetic acid and sodium metal.

Q. 43. Give the example of the neutralisation reaction of acetic acid.

Q. 44. What is sodalime ?

Q. 45. What is decarboxylation reaction?

Q. 46. What is saponification ?

Q. 47. What is soap ?

Q. 48. Write the equation of the reaction of reduction of methanal.

Q. 49. How can you convert propanone to ethanoic acid?

Q. 50. What is the colour of acetic acid.

Q. 51. When a piece of zinc is added to blue copper sulphate solution, the colour of the solution is?

Q. 52. When a piece of iron is added to blue copper sulphate solution, the colour of the solution is?

Q. 53. Which organic compound is formed when acetic acid is warmed with ethyl alchohol in the presence of concentrated H₂SO₄?

Q. 54. Give the IUPAC name of formic acid.

Q. 55. What is the smell of acetic acid?

Q. 56. What is universal indicator.

Q. 57. Name three indicators which are commonly used in a laboratory.

Q. 58. What will be the effect on a blue litmus paper when it is brought in contact with SO2 dissolved in water.

Q. 59. Fe₂O₃ + 2Al → Al₂O₃ +2Fe. This reaction is an example of which reaction.

Q. 60. What happens when

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