Stoichiometry Flashcards
Define ‘Relative mass’
The mass of an atom compared to the mass of C-12
State Avogadros number
6.02x10^23
Define a mole
6.02x10^23 of any substance
What is the formula for mass?
mass = Moles x Mr
What is the formula to calculate the number of particles of a substance?
no. of particles of x = moles x avogadros no.
What is the formula for volume?
Volume = moles x 24 (RTP)
What is the formula for concentration?
Concentration = Moles / Volume
How do we find the percentage composition of an element?
(Percentage composition)
Percentage composition of x = (mass of element in a compound / Mass of compound) x100
How do we find the percentage yield of a compound?
Percentage yield = (Yield of product / theoretical yield of product) x100
In a limiting reactant question, what do the moles tell you post-ratio ?
The number of moles of (substance) needed to fully react with (the other substance)
Give a step-by-step instruction (4) on how to get the empirical formula, starting with percentages.
> 1) Find the mass by converting % to mass
> 2) Calculate the moles by the now found mass
> 3) Find the simplest mole ration (divide all by the smallest mole)
> 4) Round
What does it mean if an ion ends with ‘ide’
It has a negative charge
What does it mean if an atom ends with “ate/ite”
It is oxidized
