chapter 14-periodic table

• elements down the group has the same amount of valence electrons
• elements in the same group have similar chemical properties
• going down the group there is a increase in metallic properties and a decrease in non-metallic properties
• metallic properties are high density, high melting and boiling point and good conductors
• alkali metals are soft and can be cut easily
• alkali metals have low meling and boiling points
• alkali metals have low densities
• alkali metals are high reactivity, thus they are stored in oil to prevent them from reacting with air and water
• order of reactivity of alkali metals lithium<sodium<potassium<rubidium<caesium<francium
• halogens have low density and are coloured
• more reactive halogens will replace less reactive halogens in its halide solution
• helium is used to make balloons float
• neon is used to make neon lights
• argon is blown through molten steel to remove excess carbon
• transition metals have high melting points and high densities
• transition metals and their compunds act as good catalysts
• transition metals form coloured compounds