[Part 2]- C2- the periodic table 🧪

• all group 7 elements, have seven electrons in their outer shell.

• Group seven elements form molecules, with two atoms which are joined by a covalent bond.

• group seven are called the halogens.

• the melting and boiling points of group seven increases as you move down the group.

• as you move down group seven, the relative molecular mass increases. [the molecules get bigger]

• as you move down group seven, the relative molecular mass increases.

• The halogens are all non-metals.

• group seven elements form covalent compounds, when they react with other non-metal atoms.

• when group seven elements react with a metal, the group seven element: gains one electron and forms a negatively charged -1 ion.

• as you move down group seven, the reactivity of the halogens decreases • This is because its harder to gain an extra electron, as there is a greater distance from the nucleus aswell as shielding by internal electrons.

Fill in the gaps: A more reactive halogen, can displace a less reactive halogen from an aqueous solution of its salt.

• group seven [the halogens] have a higher relative atomic mass.