C4 - Quantitative Chemistry Flashcards
1
Q
What is the equation for atom economy?
A
Mr of desired product/Mr of all reactants * 100
2
Q
What is the equation for volume of gas?
A
mass/Mr * 24dm^3(24000cm^3)
3
Q
What is the equation for percentage yield?
A
actual yield/theoretical yield * 100
4
Q
What is the equation for moles?
A
moles=mass/Mr
5
Q
What is the equation for concentration?
A
concentration=mass/volume(dm^3)
6
Q
What is the equation for concentration(moles)?
A
concentration=moles/volume(dm^3)
7
Q
What is the equation for the percentage of an element?
A
Ar/Mr * 100
8
Q
What is a limiting reagent?
A
- Reactant that is completely used up that limits the amount of products
9
Q
Why is not always possible to obtain the calculated amount of product?
A
- Reaction may not be completed because it’s reversible
- Some product may be lost when separated
- Some reactants may react in different ways
10
Q
Why do some reactions appear to increase in mass?
A
- When substances react with gases in the air the mass will increase
11
Q
Why do some reactions appear to decrease in mass?
A
- When a gas is a product it is released into the atmosphere
