C6-groups in the periodic table

• Group 1 metals are soft and malleable and form positive ions. Reffered as the alkali metals.
• The reactivity of group 1 increases down the group due to an increase in atomic radius, which leads to weaker metallic bonds and increased electron affinity.
• Group 7 are known as the halogens and are very reactive.
• Group 0 are known as the noble gasses as they are inert and non-reactive.
• physical properties of the alkali metals:

  They are soft and have relatively low melting points
• Write the general equation for a metal reacting with water

  Metal + water → metal hydroxide + hydrogen
• What would you observe when an alkali metal reacts with water?

  Fizzing, metal moves around on the surface of the water. Potassium will have a lilac flame
• Why are the noble gases chemically inert?

  They have a full outer shell of electrons
• properties of the noble gases

  Inert, low density, non-flammability
• boiling point decreases as go down group 0
• chlorine at room temperature is a pale yellow green gas
• bromine at room temp is a red brown liquid
• iodine at room temp is a grey solid
• boiling point increases as you go down group 7
• lithium + water

  FIZZES steadily
• sodium+water

  melts into a ball and then fizzes quickly
• pottasium + water

  gives off sparks and hydrogen burns with lilac flame
• alkali metal + water

  metal hydroxide+hydrogen
• alkali metal+chlorine

  Metal chloride (salt)
• alkali metal + oxygen

  metal oxide
• halogens exist as diatomic molecules
• chemical test for chlorine

  -damp litmus paper is bleaches and turns white
• what do the halogens form when reacted with metal

  -ionic compounds

  -become metal halides -”ine” becomes “ide”
• displacement reactions

  -more reactive halogen replaces the less reactive one
• properties of noble gases

  -inert=argon used aas a sheild gas in welding

  -low density=helium used in balloons and airships

  -non-flammability=argon,krypton and xenon inside light bulbs-stops filament burning away
• Why does reactivity increase as you go up group 7?

  The outer electron is more easily gained because the electron shell is closer  to the nucleus so the nuclear attraction is higher.
• What happens to group 7 atoms when they react in terms of electrons?

  The atom gains an outer shell electron to form an ion with a 1- charge
• Write a general equation for a halogen reacting with hydrogen

  Halogen + hydrogen → hydrogen halide
• What is formed when a halogen reacts with a metal?

  a metal halide

  What is formed when a halogen reacts with hydrogen?

  a hydrogen halide