paper 1 memorise Flashcards
(68 cards)
how does reactivity change in group 1?
reactivity increases as you go down
what happens when the first 3 alkali metals react with oxygen (O2)?
react rapidly as you go down, forms metal oxides
what happens when the first 3 alkali metals react with chlorine?
forms metal chloride e.g. sodium chloride
what happens when the first 3 alkali metals react with water?
see effervescence so gas is being produced, it forms an alkaline solution, forms metal hydroxide and hydrogen
what happens when chlorine, bromine and iodine react with non-metals?
forms covalent compounds e.g. hydrogen bromIDE
what happens when chlorine, bromine and iodine react with metals?
forms ionic compounds e.g. lithium bromIDE
what are the properties of transition elements?
- hard, strong
- high MP
- high density
- less reactive than group 1 with oxygen, chlorine and water
- can form ions with different charges
- can form coloured compounds
- are used as catalysts
explain ionic bonding
transferring electrons where the particles are oppositely charged ions
explain covalent bonding
the particles are atoms which share pairs of electrons
explain metallic bonding
the particles are atoms which share delocalised electrons
describe the structure of an ionic compound
it is a giant structure of ions, ionic compounds are held together by strong electrostatic forces of attraction between oppositely charged ions which act in all directions in the lattice
what are the limitations of a state diagram?
in the model there are no forces, that all particles are represented as spheres and that the spheres are soli
what are the limitations of a dot and cross diagram?
do not tell the shape of the molecule
what are the advantages of a dot and cross diagram?
one atom’s electron is shown as a dot the other as a cross so its clear where each electron is coming from
what are the limitations of a stick diagram?
bonds are shown as sticks so no idea where electron is coming from, don’t show the outer electrons that are not in bonds, do not show the shape of the molecule
what are the advantages of a ball and stick diagram?
you can see the 3D structure
what are the limitations of a ball and stick diagram?
the ions are shown as widely spaced whereas the ions are packed together
what are the limitations of 3D diagram?
only show a small part of the lattice which can mislead that they are much smaller
why are metals are good conductors of thermal energy?
because energy is transferred by the delocalised electrons
describe the structure of graphite
each carbon atom forms three covalent bonds with three other carbon atoms, forming layers of hexagonal rings which have no covalent bonds between the layers
describe the structure of diamond
each carbon atom forms four covalent bonds with other carbon atoms in a giant covalent structure, so diamond is very hard, has a very high melting point and does not conduct electricity.
what is graphene?
a single layer of graphite
what is a fullerene?
molecules of carbon atoms with hollow shapes
what is the structure of fullerenes?
based on hexagonal rings of carbon atoms but they may also contain rings with five or seven carbon atoms. The first fullerene to be discovered was Buckminsterfullerene (C60 ) which has a spherical shape