The code letters A to Z have been assigned to the first 26 elements of the periodic table. They do not correlate in any way with the real symbols for these elements. Study the clues, based on experimental data, which are given below. Then place the code letters in their correct position on the table. Hint: First find out which group each family represents, then arrange the elements within the groups.


1. The following elements belong together in families:



2. The element N has 4 valence electrons.

3. UA2 is the formula for a compound. In this compound, there are two atoms with an atomic number of 8.

4. X is a noble gas.

5. I is an alkali metal.

6. M, having 3 half-filled orbitals, can form three bonds.

7. H is an alkaline earth metal.

8. W is a halogen.


9. The ionization energy of T is greater than that of L, but less than that of H.

10. Y is less metallic than M.

11. Qs atomic radius is greater than that of K.

12. The electrons of atom U are distributed over three energy levels.

13. V is a liquid, whereas W is a gas at room temperature.

14. The compound IW is less stable than FW. More metallic elements tend to form more stable compounds.

15. Atom J has two protons.

16. Z has the lowest atomic mass in its group.

17. The electronegativity of element O is the largest on the periodic table.

18. The density of S is 0.53 and that of I is 0.97. The metal with the most number of energy levels has the highest density.

19. R has an outer energy level electron configuration of 3s2 3p1.

20. The products of P2A and NA2 are formed when a candle burns.

21. E contains 10 protons.

22. The electrons of C are distributed over four energy levels.

23. The electron configuration of X is the same as that of the ion F+1. (Please note that this refers to the code letter F, not fluorine.)


Link to the blank puzzle to put your answers on


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