Amount Of Substance Flashcards
Relative atomic mass (Ar)
The weighted average mass of an atom of an element, taking into account its naturally occurring isotopes, relative to 1/12 the relative atomic mass of the an atom of carbon-12
Relative molecular mass
Mass of the molecule compared to 1/12 the relative atomic mass of an atom of carbon-12
Empirical formula
Represent the simplest whole number ratio of the atoms of each element present in a compound
Molecular formula
Actual number of atoms in each element in a compound
Atom economy definition
A measure of the proportion of reactants that are converted into desired products rather than waste products
Yield definition
Practical efficiency of the process
how much product is actually made in a chemical reaction
Mole definition
A quantity of substance that contains 6.022x10^23 particles (number of particles in 12g of carbon-12
equation for moles, Mr and mass
moles = mass/ Mr
equation for moles, volume and concentration
moles = cv
what is the ideal gas equation
P(Pa)V(m3) = nR(8.31)T(K)
what is an ideal gas
ideal gases are in random motion as there are no intermolecular forces
has perfect elastic conditions where energy will be lost
benefits of high yield
maximises profit by making as much product as possible in the quickest time
more environmentally friendly as less energy required to make products so crude oil is reserved
% error equations (2)
= (theoretical - actual)/theoretical x 100
= +- error value/value measured x 100
how to calculate % total error
adding the % errors of each piece of apparatus
% atom economy equation
= Mr (including balancing numbers) of desired product/ total Mr of products
