Topic 2 - Bonding, Structure and Properties of Matter Flashcards
what is ionic bonding
ionic bonding is the transfer of an electron to another element causing a bond
what happens when a non-metal and metal react (charges)
the metal atom loses an electron to form a positively charged ion and the non-metal becomes a negatively charged ion
what are the similar properties for ionic compounds
same high melting point and boiling point
when melt the ions are free to move with an electric current
when dissolved in water the ions separate, free to move so carry electric current.
what is a covalent bond
when non-metals react they share electrons to make a covalent bond.
what are the properties of covalent bonding
they are simple molecular structures
strong covalent bonds, weak forces of attraction
low melting and boiling to separate them from each other
what are polymers
they are long chains of repeating units with strong covalent bonds
what is a giant covalent structure
they are macromolecules with high melting and boiling points. dont contain charged particles so dont conduct electricity
what is diamond’s giant covalent structure
each carbon forms four covalent bonds in a ragid way
what is graphites giant covalent structure
each carbon forms three covalent bonds to create layers of hexagons
what is silicon dioxides giant covalent structure
each silicon forms one covalent bond with oxygen to create sand
what is metallic bonds giant structure (attractions)
the electrons of the outer shell of the atoms are delocalized. have strong forces of electrostatic attractions between positive metal ions and negative elctrons
why are metals good conductors
they have a delocalized outer electron that carries electrical current and thermal energy through the whole structure
moles equation
moles = mass(g) / Mr(atomic mass)
how to work out the moles of a compound
add up the relative atomic masses
divide the mass by what you just added up
equals moles
