5.2 Quantitative Analysis

Allows you to find the exact volume of acid needed to neutralise an alkali or vice versa

1- Use a pipette to measure a set volume of acid/alkali of unknown concentration into a flask and add an indicator 2- Fill the burette with a known concentration of acid/alkali 3- Use the burette to slowly add the liquid with known concentration to the liquid with unknown concentration 4- When the indicator changes colour the unknown concentration substance has been neutralised. 5- Record the volume of known concentration liquid and repeat until you get concordant titres

The volume recorded in titration

-Swirl the flask regularly -Place the conical flask on a white tile -Read from meniscus -Add burette solution one drop at a time near end point -Make sure no air bubbles in burette -Wash inside of conical flask with deionised water -Wash burette with solution before titration

So that the colour change is easier to see

At eye level from the bottom of the meniscus

The volume occupied by one mole of gas

Molar volume = gas volume / number of moles

Under the same conditions the same number of moles of different gases will occupy the same volume

24dm3

What percentage of the mass of the reactants has been converted into the desired product when manufacturing a chemical

Atom economy = (total Mr of desired products) / (total Mr of all products) x100

All the atoms in the reactants have been turned into useful products

-Unsustainable -Not very profitable

-They use up resources quickly -They make lots of waste resources that have to disposed of somehow

Raw materials can be expensive to buy and waste products can be expensive to dispose of responsibly

Find a use for the waste products rather than throwing them away

-Atom economy -Percentage yield -Rate of reaction -If the reaction’s reversible

The mass of product you’d make if all reactants were converted to products

The amount of product you get from a reaction

Percentage yield = (actual yield) / (theoretical yield) x100

-Incomplete reactions -Practical losses -Unwanted reactions

If not all reactants are converted to product, the reaction is incomplete and the yield will be lower than expected

You always lose a bit when you transfer chemicals between containers- some is left on the inside surface of the old container