Periodic Classification of Elements

Grade 10 Science — Periodic Classification of Elements: 25 practice questions with instant scoring and explanations.

1. Dobereiner's triads consist of:
2. According to Newlands' law of octaves, elements similar in properties occur every:
3. Mendeleev left gaps in his periodic table because:
4. The modern periodic table is arranged by:
5. In the modern periodic table, elements in the same group have:
6. As we move across a period from left to right, atomic radius:
7. Which property increases down a group in the periodic table?
8. Metallic character in the periodic table:
9. Which of the following elements is most electronegative?
10. The atomic number of an element is determined by:
11. Valency of an element is related to:
12. Noble gases have a valency of:
13. The first element to be predicted by Mendeleev was:
14. Elements in Group 17 are called:
15. Which block of the periodic table contains transition metals?
16. Electronegativity values are highest for:
17. As we go down Group 1, the atomic radius:
18. Which of the following is a characteristic of transition metals?
19. The period number indicates:
20. In the periodic table, lanthanides and actinides are placed:
21. Which element has the highest first ionisation energy?
22. The trend in atomic radius across Period 2 is:
23. Mendeleev's prediction about Eka-silicon was validated by the discovery of:
24. Which property is incorrectly matched?
25. In going from Na to Cl across period 3, the atomic radius: