chem chp 6 chemical formulae and equations

chemical formula

monoatomic elements

diatomic molecules (elements)

ends with en and ine (not ide) so it is elements not ions

ends with ate and ide

ide —→ ion

polyatomic molecules

chemical formula of compounds

hydrogen in acids is H+

carbon monoxide is CO

nitrogen monoxide is NO

nitrogen dioxide is NO2

valences of an element and valences from roman numerals

must memorise **

silver —> Ag+

zinc —> Zn2+

polyatomic ions (must memorise)

ammonium is not the same ammonia

ammonium is the ion

ammonia is the gas

if a polyatomic ion is more than 1, than must draw bracket

deducing chemical formulae of compounds

word equations

balancing chemical equations

ionic equations

find the ions charge by doing the criss cross thing backwards

special cases of aqueous covalent substances

acid ionizes in water and split into ions as acids contains hydrogen which is H+ in acids