Quantitative chemistry Flashcards
How can you calculate the percentage mass of an element in a compound
Mr of atoms in that element/ Mr of the compound
What is a mole
A specific number of atoms- 6X10^23
What is the conservation of mass in equations
Mass of products = mass of reactants
If mass seems to change, what is the likely explanation during a reaction
Gas has left the container, or gass has formed a compound with something in the container
What equation links moles, mass and Mr
Moles = Mass / Mr
When do reactions stop
When there is a limiting reactant
How can you calculate the limiting reactant
It’s the one with the least moles
What volume does one mole of gas take up at room temperature
24dm^3
What is the formula for calulating volume of gas
Volume of gas = (mass of gas/ Mr of gas) X 24
What is concentration
A measure of how ‘crowded’ particles are
How do you measure concentration (2)
Mass of solute/ Volume of solvent
OR moles of solute/ volume of solvent
What is atom economy
The percentage of useful products in a reaction
How do you calculate atom economy
Relative formula mass of desired products/ Relative formula mass of all reactants
How do you increase atom economy
By increasing the products sold/ useful products
What is percentage yield
The real life mass of products actually made/ The maximum theoretical mass of products
