C4 relative masses moles and expressing concentration Flashcards
what is the law of conservation of mass
the mass of the products equals the mass of the reactants
how is mass conserved (kept the same )
no atoms are lost or made during a chemical reaction
what is the relative formula mass
the sum of the relative atomic masses of the atoms in the numbers shown in the formula
what happens when reactions involve a change in mass
this happens when reactions are carried out in a non-closed environment and include a gas that can enter or leave
what are half equations used for
to show what happens to one reactant in a chemical reaction
what are ionic equations used for
simplify complicated equations
what are chemical amounts measured in
moles
what is the Avogadro’s constant
The number of atoms, molecules or ions in a mole of a given
substance is the Avogadro constant
6.02 x 10^23
what is the equation for mols
mols = mass / relative formula mass
what is the equation for concentration
mass / volume
what is the limiting reactant
when one chemical is used up it stops the reaction going any further
