1. Some crystals of copper sulphate were dissolved in water. The color of the solution obtained would be:

2. When Zinc pieces are added to dilute HCl taken in a test tube, then:

3. PbS reacts with ozone (O3) and forms PbSO4. As per the balanced equation, molecules of ozone required for every one molecule of PbS is/are:

4. Chemically rust is:

5. In the reaction: PbO + C → Pb + CO

6. A substance which oxidizes itself and reduces other is known as:

7. The reaction between lead nitrate and potassium iodide present in aqueous solution is an example of

8. What happens when dilute hydrochloric acid is added to iron filling?

9. In an electrolytic cell where electrolysis is carried, cathode has:

10. In the decomposition of lead (II) nitrate to give lead (II) oxide, nitrogen dioxide and oxygen gas, the coefficient of nitrogen dioxide (in the balanced equation) is

11. Which of the following is not a balanced equation?

12. Dissolving sugar is an example of:

13. We store silver chloride in dark colored bottles because it is

14. The reaction H₂ + Cl₂ → 2 HCl represents:

15. Copper displaces which of the following metals from its salt solution:

16. Which of the following statements about the given reaction are correct? 3Fe (s) + 4H₂O (g) → Fe3O₄ (s) + 4 H₂ (g)(i) Iron metal is getting oxidised (ii) Water is getting reduced (iii) Water is acting as reducing agent (iv) Water is acting as oxidising agent

17. In the double displacement reaction between aqueous potassium iodide and aqueous lead nitrate, a yellow precipitate of lead iodide is formed. While performing the activity if lead nitrate is not available, which of the following can be used in place of lead nitrate?

18. A dilute ferrous sulphate solution was gradu¬ally added to the beaker containing acidified permanganate solution. The light purple colour of the solution fades and finally disap¬pears. Which of the following is the correct explanation for the observation?

19. In an electric cell where electrolysis is carried out, anode has:

20. The colour of phenolphthalein in acidic medium is-

21. The gas which burns with a pop sound –

22. Milkiness of limewater disappear when excess CO2 is passed due to the formation of

23. The acid present in tomato is-

24. The common name for the substance used as antacid-

25. Calcium carbonate reacts with hydrochloric acid to form X, Y ,Z. What areX, Y, Z ?

26. When you clean a metal vessel with tamarind the reaction taking place is: Metaloxide+X——– → Salt+Water. What is X here?

27. Brine is an

28. Sodium carbonate is a basic salt because it is a salt of a

29. Nettle sting is a natural source of which acid?

30. Tooth enamel is made up of

31. Rain is called acid rain when its:

32. Farmers neutralize the effect of Acidity on soil by adding

33. In which pH range does our body work to survive in the atmosphere?

34. The pH of a solution is 7. How can you increase its pH?

35. Which gas is evolved when acids react with metals?

36. Which of the following gives the correct increasing order of acidic strength?

37. One of the constituents of baking powder is sodium hydrogen carbonate, the other constituent is

38. The pH of three solutions X, Y and Z is 6, 4 and 8 respectively. Which of the following is the correct order of acidic strength?

39. What is gastric acid present in the stomach composed of?

40. Aluminium is used for making cooking utensils. Which of the following properties of aluminium are responsible for the same? (i) Good thermal conductivity (ii) Good electrical conductivity (iii) Ductility (iv) High melting point

41. The most abundant metal in the earth’s crust is

42. The poorest conductor of heat among metals is

43. Which property of metals is used for making bells and strings of musical instruments like Sitar and Violin?

44. Al₂O₃ + 2NaOH → …… + H₂O

45. Which of the following is the correct arrangement of the given metals in ascending order of their reactivity? Zinc, Iron, Magnesium, Sodium

46. The pair of linear equations 3x+4y = 12 and y=4 has

47. In an A P ,if d= -4 , n= 7, an = 4 then a is

48. The ratio of the lengths of sides of an equilateral triangle and its height is

49. Which of the following can not be a right triangle

50. If the radius of the circle is increased three times how many times will it circumference increased

51. In a single throw of two dice the probability of getting a total of 8 is

52. The zeroes of a polynomial 3x²-2x-5 are

53. If the difference of mode and median of a data is 24, then the difference of median and mean is

54. For a frequency distribution, mean, median and mode are connected by the relation

55. The distance between two parallel tangents of a circle of radius 3 cm is:

56. Volume and surface area of a sphere are numerically equal, then radius of sphere is

57. The value of k for which x, 2x+k, 3x+6 are any three consecutive terms of AP is

58. Find the zeroes of the quadratic polynomial x² – 4x + 3.

59. If p,p+2 and 2p-3 are three consecutive terms of an AP ,find the value of p .

60. A number is selected at random from the numbers 1 to 30. The probability that it is a prime number is

61. .If the nth term of an AP is 2n+1 , then the sum of first n terms of the AP is

62. The three terms of an AP are respectively 3y-1, 3y+5, and 5y+1. Then y equals to

63. The perimeter of a triangle with vertices (0,4) , (0,0) and (3,0)

64. The probability that non – leap year has 53 Sundays is

65. The probability that leap year has 53 Sundays is

66. The pair of equations x = a and y = b graphically representing lines which are :

67. If 11 times the 11th term of an A.P. is equal to 7times its 7th term, then its 18th term will be :

68. For a given data with 50 observations the ‘less than ogive’ and the ‘more then ogive’ intersect at (15.5, 20). The median of the data is

69. In a throw of two dice, the probability of getting a sum of 10 is :

70. The radii of bases of a cylinder and a cone are in the ratio 3 : 4 and their heights are in the ratio 2 : 3. The ratio between the volume of cylinder to that of cone is

71. The 10 th term of the AP 2, 7 , 12 , … is

72. Sides of two similar triangles are in the ratio 4 : 9 areas of these triangles are in the ratio

73. CosecA /secA is

74. The total number of outcomes if 3 dices are thrown simultaneously is

75. A tangent PQ at a point P of a circle of radius 5 cm meets a line through the centre O at a point Q so that OQ = 12cm , length PQ is

76. Construction of a cumulative frequency table is useful in determining the

77. Which of the the following can be the probability of an event?

78. Euclid’s division lemma states that for two positive integers a and b, there exist unique integers q and r such that a = bq + r, where r must satisfy

79. If one of the zeroes of the cubic polynomial ax3 + bx² + cx + d is zero, the product of then other two zeroes is

80. If one zero of the quadratic polynomial x² + 3x +k is 2 , then the value of k is :

81. x = a and y =b is the solution of the linear equation x- y = 2 and x + y = 4, then the value of a and b are :

82. If one root of the quadratic equation 4x² – 2x + (k-4) = 0 be the reciprocal of the other, then k = ……..

83. If 18, a, b, -3 are in A.P, then a +b = ………

84. If tanA = cot (30 + A), then, A= …..

85. The area of the circle that can be inscribed in a square of side 10cm is ….

86. Two isosceles triangles have equal angles and their areas are in the ratio 16:25. The ratio of their Corresponding heights is

87. If p and q are the roots of the equation x²-2x+1=0 then

88. If PA and PB are tangents to the circle with centre O such that

89. If point P(x, y) is equidistant from A(5,1) and B(-1,5), then

90. The area of the largest triangle that can be inscribed in a semi-circle of radius ‘r’ is