Quantitive Chemistry Flashcards
Calculate the MR of H2 S04
2+32+4×16 = 98
How would you calculate percentage by mass of an element in a compound?
Percentage mass brackets, total MR of the element /MR of the compound) times 100
What is the law of the conservation of mass?
The total mass or reactants is equal to the total mass of the products
When does the law of conservation of mass appear to be violated?
When one of the reactants or products is a gas?
Give the equation that links mass moles and MR
mass =mr moles
How many particles in one mole
6.02 x 10 to the power of 23
Unit of concentration
Mol/dm3
What’s the equation to calculate moles, when given concentration and volume?
Moles equals concentration times volume
What does a high concentration mean?
A large number of solute particles per unit volume
What is the equation to calculate yield
Yield =actual mass divided by theoretical mass x100
Give three reasons why might yield not be 100%
An incomplete reaction. Some products might be lost side reaction.
Give the equation to calculate atom economy
Ask economy equals Mr of useful product /total MR of reactants) x100
Apart from atom economy, what are the factors are important in choosing a reaction pathway
Yield environmental impact of reactants or products rate of reactions
What volume does one mole of gas occupy
24dm 3
Give the equation that calculates the volume of gas, when given the number of moles
Volume (dm3) =moles x24
