1.  Boron exists as two stable isotopes; ¹⁰B(19%) and ¹¹B(81%). Find out the average atomic weight of boron in the periodic table

2. What will be the volume of the mixture after the reaction

3. Which of the following contains same number of carbon atoms as are in 6.0 g of carbon (C – 12)?

4. Elements X and Y combine to form two compounds XY and X₂Y. Find the atomic weight of X and Y, if the weight of 0.1 moles of XY is 10g and 0.05 moles of X₂Y is 9g

5. The prefix 10¹⁸ is

6. The percentage of nitrogen in urea is about

7.  A container has an equal mass of H₂, O₂ and CH₄ at 27℃, the ratio of their volume is

8. For the reaction Fe₂O₃ + 3CO₂ → 2Fe + 3CO₂, the volume of carbon monoxide required to reduce one mole of ferric oxide is

9. Which of the following weighs the most?

10. Which of the following cannot give iodometric titrations

11. There are two chlorides of sulphur S₂Cl₂ and SCl₂. What is the equivalent mass of S in SCl₂

12. What is the normality of a 1 M solution of H₃PO₄

13. Number of atoms in 558.6 g Fe (Molar mass Fe = 55.86 g mol^-1) is

14. A symbol not only represents the name of the element but also represents

15. The increasing order of molarity with 25 gm each of NaOH, LiOH, Al(OH)₃, KOH, B(OH)₃ in same volume of water?

16. The sulphate of a metal M contains 9.87% of M. This sulphate is isomorphous with ZnSO₄.7H₂O. The atomic weight of M is

17. The approximate atomic weight of an element is 26.89. If its equivalent weight is 8.9, the exact atomic weight of the element would be

18. How many mL of water must be added to 200 mL of .65 M HCL to dilute the solution to .20 M

19.  If we consider that 1/6, in place of 1/12, mass of carbon atom is taken to be the relative atomic mass unit, the mass of one mole of a substance will

20. The percentage of copper and oxygen in samples of CuO obtained by different methods were found to be the same. This illustrate the law of