sc9 reacting masses Flashcards
in a chemical reaction does the total mass change or stay the same
mass is aways conserved
why in some chemical reactions does it seem that mass has increased
because the gas is a reactant and the products are solids, liquids or aqueous. before the reaction the mass of the gas isnt accounted for because its floating in the air
why in some chemical reactions does it seem that mas decreases
because one of the products is a gas and all reactants are solids, liquids or aqueous, if the vessel isnt enclosed the gas just escapes after the reaction
how do you calculate the relative formula mass?
the relative atomic masses (the number at the top of the element on the periodic table) of all the atoms in its formula added together
how do you calculate the empirical formula
the simplest ratio of the atoms, divide the numbers by the biggest number that goes into all of them
what is avogadro’s constant
6.02 x 10^23
how do you calculate numbers of particles
multiplying avogadro’s constant by the number of moles
how do you calculate the number of moles
mass in g / relative formula mass
how do you calculate concentration
mass of solute/ volume
