C2 The Periodic Table

3. a tiny particle with a negative charge
8. a substance made as a result of a chemical reaction.
11. all the elements in the columns (labelled 1 to 7 and 0) in the periodic table
12. most reactive non metal in group 7
13. the first noble gas
14. most reactive metal in group 1
16. atoms that have the same number of protons but different number of neutrons,
17. the very unreactive gases found in Group 0 of the periodic table.
18. a charged particle produced by the loss or gain of electrons
21. a substance we start with before a chemical reaction takes place
22. the least reactive non metal in group 7

1. a transition metal that forms blue or green salts.
2. the elements found in Group 7 of the periodic table
4. least reactive metal in group 1
5. a substance made when two or more elements are chemically bonded together
6. a substance made up of only one type of atom.
7. metal element from the central block of the periodic table
8. an arrangement of elements in the order of their atomic numbers, in a table.
9. a mixture of indicators that can change through a range of colours to show how strongly acidic or alkaline liquids and solutions are
10. metal elements in Group 1 of the periodic table
15. the smallest part of an element that can still be recognised as that element
19. a structure in numbers to show the arrangement of electrons in their shells (or energy levels)
20. the number of protons (which equals the number of electrons) in an atom.