group 1 and 7 Flashcards
what happens when metals react
they lose electrons to achieve a full outer energy level, giving them the same structure as a noble gas
what ions do metals form
positive ions
how many valence electrons to group 1 metals have
1
what happens when group 1 metal react with oxygen in they air
they react become dull
properties of group 1 metals
- very low density
- they are very soft
- they are shiny and silvery on the inside but become dull when they react with oxygen in the air
- they melt and boil at low temperatures
trend of reactivity for group 1 metals
the react more rapidly as you go move down group 1 as there is a greater distance between the valence electron and the nucleus and the outer electron is more shielded from the nucleus by the internal energy levels this means that the outer electron is less attracted to the nucleus so its easier to lose
how do group 1 metals react with water
they start to float, fizz and move vigorously and produce a metal hydroxide, as you go down the group the reaction happens more quickly and vigorously, and when potassium reacts with water it produces a lilac flame
why are group 1 metals alkaline
they produce hydroxide which is a colourless solution with a high pH
how do group 1 metals react with chlorine gas (or non metals)
they produce metal chloride ( e.g lithium chloride), the reactions get more vigorous as you go down the take as its easier to lose an electron and form a 1+ charge, the metal chloride also dissolves in water to form a colourless solution
trend of boiling and melting points of group 1 metals
the melting and boiling point decreases due to a decrease in the forces of attraction between the atoms
what happens when non metals react
they share a pair of electron
what is room temperature
20 degrees Celsius
trend of the boiling point and melting point of the halogens
it increases as you go down the group as the molecules become larger. the intermolecular forces become stronger.
properties of group 7 halogens
- toxic non metals that form coloured vapours
- poor conductors of heat and energy
- they are diatomic molecules ( they are made of pairs of the same atoms)
- low bp and mp
-a more reactive halogen will displace a less reactive halogen from an aqueous solution of its salt
colour of chlorine
pale green
colour of iodine
dark red/ brown
colour of bromine
yellow
trend of the reactivity of group 7 halogen
the reactivity decreases as you go down the group as the distance between the outer energy level and the nucleus and the outer energy level is shielded from the nucleus by internal energy levels reducing the attraction between the nucleus and outer electrons so it is harder for the halogens to attract an electron to its outer energy level
properties of transition metals
- have high densities
- have high melting points
- good conductors of electricity
- can from coloured compounds
- can be used as catalysts
examples of coloured compounds
copper - blue
nickel - pale green
chromium - dark green
manganese - pale pink
why are transition metals good building materials
as they have a high density and corrode very slowly (and due to its other properties)
