2 2 group 7 halogens

Group 7 of the Periodic Table is the called the halogens.

Fluorine is in Group 7 of the Periodic Table because it has 7 electrons in its outer shell.

The colour and state of chlorine at room temperature is a pale green gas.

The colour and state of bromine at room temperature is a brown liquid.

The colour and state of iodine at room temperature is a grey solid.

The colour and state of fluorine at room temperature is a yellow gas.

Going down the group, melting points of the halogens increases.

A halogen displacement reaction is one where a more reactive halogen displaces a less reactive halogen from an aqueous solution of its halide.

The word equation for the displacement reaction between potassium bromide and chlorine is: potassium bromide + chlorine → potassium chloride + bromine

The balanced symbol equation for the reaction between potassium iodide and bromine is: Br2 + 2KI → 2KBr + I2

Iodine cannot displace chlorine from potassium chloride because iodine is less reactive than chlorine.

Chlorine has a higher melting point than fluorine because there are stronger intermolecular forces which need more energy to overcome.

The charge of the ions formed when halogens react with Group 1 metals is 1-.

Reactivity is the tendency of a substance to undergo a chemical reaction by losing or gaining electrons.

Halide ions are ions formed when halogen atoms gain an electron, carrying a 1- charge

The trend in reactivity of the halogens is, going down the halogen, reactivity decreases.

The electronic configuration of a chlorine atom is 2.8.7.

Fluorine is the most reactive halogen because it has the fewest shells so it is easier for the nucleus to attract an electron.

False. It becomes harder for halogen atoms to gain electrons as you go down the group making them less reactive.

Reactivity decreases going down Group 7 because the atoms have more shells, meaning there is a less attraction between an incoming electron and the positive nucleus making it harder to gain an electron.