1.Potassium chlorate decomposition occurs in the temperature range between

2.UNESCO inaugurated the celebration of 2019 as the International Year of the periodic table of chemical elements to celebrate its completion of how many years?

A. 100
B. 150
C. 75
D. 50
E. None of the above/More than one of the above

3. Which of the following is the most common element in the Universe?

4. According to Newland's law of octaves, beryllium resembles which of the following elements?

5. Which is the most abundant element after oxygen?

6. Which of the following elements was first produced artificially?

7. Which of the following is not a type of element?

A. Metals
B. Non-metals
C. Gases
D. Metalloids
E. None of these/More than one of these

8. Approximately how many different chemical elements exist on the earth? 

9. Fluorine, chlorine and bromine belong to group
17. They have same

10. Correctly match the following.

11. In modern periodic table, which of the following statements about atomic radius are true?

1. Increases from top to bottom 
2. Decreases from top to bottom
3. Increases from left to right
4. Decreases from left to right

Find out the correct option.

12. Assertion (A) In the periodic table of chemical elements, electron affinity is always found to increase from top to bottom in a group. Reason ( ) In a group, the atomic radii generally increases from top to bottom.

Choose the correct options given below.

13. Consider the following statements with reference to the periodic table of chemical elements.

1. Ionisation potential gradually decreases along a period.
2. In a group of elements, electron affinity decreases as the atomic weight increases.
3. In a given period, electronegativity decreases as the atomic number increases.
   Which of these statement(s) is/are correct?

14. What is the usual property of oxides of group 3 and 4?

15. Match List I with List II and select the correct answer by using the codes given below the lists.