Periodic Trends Flashcards
What happens to the alkaline metals as you go down the group (1)?
They become more dense Boiling and melting points decrease Want to lose 1 electron so lose outer shell to form +ion Similar physical and chemical properties Are more reactive going down the group
What are the properties of alkaline metals?
Soft
Shines
Low boiling and melting points
Conduct electricity
What reaction occurs when alkaline metals react with oxygen?
Oxidation reaction
Eg. lithium + oxygen= lithium oxide
What gas is produced when alkaline metals react with water?
Hydrogen (squeaky pop)
Eg. Lithium + water = lithium hydroxide + hydrogen
What are the halogen group?
Salt formers, always exist in pairs ( diatomic)
Non metals
Don’t conduct electricity
Brittle, crumbles, poisonous and smelly
What are the properties of the halogen group (7)?
Boiling and melting point increase going down group
Want to gain 1 electron to fill outer shell forming - ion
Reactivity decreases going down group ( harder to pick up passing electrons)
What reactions take place in group 7?
Displacement reactions
More reactive halogens will displace less reactive
Chlorine will displace bromine and iodine
Bromine will displace iodine but not chlorine
What are the alkaline earth metals?
Group 2 metals
Same properties as group 1 but less reactive
What are the properties of the Nobel gases?
Increase density and boiling point going down the group
Inert (not reactive)
Monatomic
Used in lighting
What are the trends going across the periodic table ( group 3)
Atomic radius ; decreases Atomic size; decreases Ionisation energy ; increases Electro negativity ; increases Melting point ; Na to Si increase P, S, Cl and Ar lower boiling point
What non metal conducts electricity?
Graphite, conducts electricity due to free carbon.
