C5.1 Flashcards
(14 cards)
What is the yield of a product?
The mass of a product made in a chemical reaction.
What is theoretical yield?
The maximum mass possible to make of a product from a given mass of reactants.
In order to calculate theoretical yield, what do you need to know?
Mass of the limiting reactant.
What is the formula used to calculate theoretical yield?
USE BALANCING NUMBERS WHEN CALCULATING Mr.
theoretical yield = {(mass of limiting reactant)/(sum of Mr for limiting reactant)} x sum of Mr for products
What is actual yield and percentage yield?
Actual yield - mass of product actually made
Percentage yield = actual yield/theoretical yield x 100
What factors affect the percentage yield?
- Reactants react in a different way than expected (e.g. a combustion reaction in the air gives a different product)
- Reaction may not go to completion - some reactants may not react or it’s a reversible reaction.
- Some product may be lost when separated from the mixture to purify.
What is atom economy?
The atom economy is how many atoms in the reactant form your desired product and it is given as a percentage.
How is atom economy calculated?
(INVOLVE BALANCING NUMBERS) Mr of desired product/Mr of all products
What is a reaction pathway?
The reaction or series of reactions for making a particular substance.
What factors affect choosing a reaction pathway/
- Yield
- Atom economy
- Usefulness of by products
- Rate of reaction
- Equilibrium position (reversible reaction or not)
What is the relationship between litres and dm^3, and between ml and cm^3
1L = 1dm3 1ml = 1cm3
How do you convert between cm3 and dm3?
cm3 to dm3 (divide by 1000)
dm3 to cm3 (multiply by 1000)
How do you convert g/dm3 to mol/dm 3?
g/dm3 to mol/dm 3 divide by Mr (vice versa)
What is the concentration formula?
n2w = cv, (amount of solute g or mol) = (concentration g/dm3 or mol/dm 3) x (volume dm3)
