Quantitative Aspects Of Chemical Change Flashcards
What is the mole?
A quantity of matter containing exactly the same number of elementary particles as there are carbon atoms in 12g of carbon- 12
What is Avogadro’s number?
The fixed number of particles within one mole of a substance
What is the value of Avogadro’s number?
6,02 x 10^23
What is molar mass?
The mass per mole of substance
What is relative formula mass?
The mass of one mole of a substance expressed in grams
What is the unit used to measure molar mass?
g.mol^-1
What is the formula used to determine the number of moles of a substance? (Using number of particles)
N
n= —
NA
What does n stand for?
Number of moles
What does N stand for?
Number of particles
What does NA stand for?
Avogadro’s number
What is the formula to determine the number of moles of a substance? (Using mass)
m
n= —
M
How can we determine M?
By using the values provided on the Periodic Table
What are stoichiometric calculations?
Calculations that are used to determine the masses and volume of reactants and products
What do balanced chemical equations give us?
The mole ratio in which substances react
What are the three steps that need to be followed when doing stoichiometric calculations?
Convert the given information into moles
Use the mole ratios of the equations to find the moles of the required substance
Convert the moles into the required information
What does the percentage composition of compounds tell us?
The percentage of the compound that a certain substance makes up
What do you use to work out the percentage composition of a compound?
The chemical formula of the substance
The relative atomic mass of the various elements making up the substance
How do you work out the percentage composition of a compound?
Molar mass of the compound
Divided by the total molar mass of the compound
Multiplied by 100
What determines the concentration of a solution?
The amount of solute dissolved in the solution
What symbols are used for concentration?
c
[substance]
What unit of measurement is used for concentration?
mol.dm^-3
What is the formula for the concentration of a substance?
n
c= —
V
If we are not given the number of moles, what formula do we use for concentration?
n
c= —
VM
How do you convert cm^3 to dm^3?
Divide by 1000
How many cm^3 is 1ml equal to?
1
How many dm ^3 is 1L equal to?
1
