Q1.Consider the following statements:
1. Maximum covalence of carbon is 4, whereas maximum covalence of silicon is 6. 2. The maximum covalence of an element is limited to 6.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2 Q2. Which is the rarest naturally occurring element of earth?
(d) Astatine Q3. What is the mass of one litre of cottonseed oil of density 926kg/m3
(a) 926 kg
(b) 92.6 kg
(c) 0.926 kg
(d) 9260 kgQ4. Which one among the following is not a mixture?
(d) SteelQ5. How many milligrams is 1 carat of diamond equal to?
(a) 100 mg
(b) 150 mg
(c) 200 mg
(d) 250 mg Q6. A student by chance mixed acetone with alcohol. This mixture of acetone and alcohol can be separated by
(b) separating funnel
(c) fractional crystallisation
(d) fractional distillationQ7. When an alkali-metal reacts with water, which one of the following gases is produced?
(c) Hydrogen peroxide
(d) Ozone Q8. Which one of the following gases, present in the air near the surface of the Earth, has maximum concentrations?
(a) Oxygen (O2)
(b) Hydrogen (H2)
(c) Nitrogen (N2)
(d) Methane (CH4)Q9. A student heated some sulphur in a spatula and collected the gas ‘X’. Which one among the following is correct about ‘X’?
(a) X is SO2 and it turns moist litmus to blue
(b) X is SO3 and it turns moist litmus to red
(c) X is SO2 and it turns moist litmus to red
(d) X is SO3 and it turns dry litmus to blueQ10. DIRECTIONS : The following questions consist of two statements, Statement I and Statement II. You are to examine these two statements carefully and select the answer to these items using the codes given below.
Statement I: Hard water does not give lather with soap.
Statement II: Calcium and magnesium salts present in hard water form precipitate with soap.
(a) Both the statements individually true and Statement II is the correct explanation of Statement I.
(b) Both the statements are individually true but Statement II is not correct explanation of Statement I.
(c) Statement I is true but Statement II is false.
(d) Statement I is false but Statement II is true. Q11. Consider the following statements:
1. Among the fertilizers used, urea contains maximum percentage of N.
2. The mixture of calcium sulphate and calcium dihydrogen phosphate is known as superphosphate of lime.
3. Potassium magnesium sulphate is called the muriate of potash.
Which of the statements given above are correct?
(a) 1 and 2 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3 Q12. When applied to the affected area, which one of the following will relieve the pain due to ant-bite or bee-sting?
(a) Lemon juice
(c) Baking soda
(d) Caustic soda
1. (a)2. (d)3. (c)4. (a)5. (c)6. (d)7. (a)8. (c)9. (c)10. (a)11. (a)12. (c)