Groups 1, 7 and 0 GapFill

Group 1 elements are called the  reactant metalsnoble metalsmicrometalsalkali metals and react with oxygen, chlorine and water. Their reactivity  increases down the groupdepends largely on their physical stateis comparable throughout the groupdecreases down the group. These metals share many properties; for example, they are all fairly  brittlemalleabletoxicelastic.

Group 7 elements are known as the halogens. A more reactive halogen  displacesovercomesdissolvesreplaces less reactive halogens in a solution. Halogens form  pathogenicsterileacidicbasic solutions when they dissolve in water and are often used as  disinfectantslubricantscoolantscatalysts.

In a common chemical test,  iodinechlorinebrominecarbon monoxide turns litmus paper white.

Halides can form coloured precipitates with silver nitrate, but at room temperature and pressure they each have their own appearance:  iodinefluorinebromineastatine is an orange-brown liquid,  fluorinebromineiodinechlorine is a dark purple/black solid, and  astatineiodinebrominechlorine is a pale yellow/green gas.

Group 0 elements are known as the  unreactantsneon gasesalkali gasesnoble gases and do not usually react. They are  harddensemagneticcolourless, and their boiling point increases down the group.