C4

C4

1. The nucleus of an atom contains protons and neutrons

2. The relative mass of a neutron is 1, and its charge is 0

3. When heated, the electrons in an atom release energy as light and the wavelengths emitted can be recorded as a line spectrum. Each element has a different pattern of wavelengths and so a different line spectrum

4. When heated, elements produce flames of a distinctive colour

5. Line spectrums can be used to identify new elements

6. Dobereiner organised the elements into groups of 3 called triads

7. Newlands' octaves were criticised because they contained elements that did not have similar properties, he mixed up metals and non-metals, and he did not leave gaps for new elements

8. Mendeleev left gaps in his table of elements for undiscovered elements

9. In the periodic table, elements are laid out in order of increasing proton number and the group number tells you how many electrons in it's outer shell

10. Rows in the periodic table are known as periods

11. The first electron shell can only contain 2 electrons

12. Ionic bonding occurs when oppositely charged ions bond

13. Ionic compounds form a regular lattice

14. Group 1 are the alkali metals, as you go down group 1, they become more reactive. They react violently with water to produce hydrogen and a hydroxide

15. Pairs of atoms are called diatomic molecules

16. As you go down group 7, the halogens become less reactive. they are very toxic

17. Chlorine is a dense green gas at room temp