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CONVERT EVERYTHING TO MOLES. What are we talking about from the units?. 3.2 g/dm 3 3.2 g 40cm 3 0.5 mol /dm 3 56 tonnes 3dm 3 0.00045 mol /dm 3. QUANTITATIVE CHEMISTRY. To ensure good titration practice for the task on Wednesday To improve manipulation of mole calculations.
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What are we talking about from the units? • 3.2 g/dm3 • 3.2 g • 40cm3 • 0.5 mol/dm3 • 56 tonnes • 3dm3 • 0.00045 mol/dm3
QUANTITATIVE CHEMISTRY To ensure good titration practice for the task on Wednesday To improve manipulation of mole calculations
Measuring Tips for Coursework • When doing a titration you are looking for readings within 0.1-0.2 of each other. e.g: 45.10cm345.45cm3 45.40cm3 • Burettes readings should be measured to 2 d.p. ending in 0 or 5. • Mean average titrations should be rounded to 1 d.p. • Never start at exactly 50cm3on your burette. • Your results will be measured against MrBoorman’s • A mean average of 45.45 should be rounded up to 45.5cm3
AN Important point on concentrations Concentrations can be measured in g/dm3and mol/dm3. It is simple to convert between them, using a triangle. 4 mol/dm3of NaOH 40 0.1 mol/dm3 g 4 g/dm3 of NaOH mol Mr
Mole calculations You add a 30cm3 sample of 0.8 mol/dm3 H2SO4 to a volumetric flask, and top up to the 250cm3 mark with distilled water. • How many moles of H2SO4 in a 25cm3 sample of your new diluted solution? • How many moles of KOH are needed to react with the solution in question 1? • Through titration, a scientist found that 18.5 cm3 of KOH solution was needed to neutralise the acid. What is the concentration of the KOH solution?
Mass units It is relatively easy to negotiate volume. It is either 200cm3 or 0.2 dm3 (just divide by 1000) Mass can be given in: tonnes = 1 x 106 g (1’000’000 g) kg = 1 x 103g (1’000 g) g = 1 g (ALWAYS CONVERT TO GRAMS) mg = 1 x 10-3g (0.001 g) μg = 1 x 10-6g (0.000001 g)
5 minute help sessions Pick your next worst subject, and Mr Boorman will go through it with you. 5 minutes with each student. If your problem is a lack of knowledge. Spend the time revising it.
Produce an Actual Revision plan 1) Write down dates 2) Give dates to each topic 3) Decide if you have actually remembered it 4) Plan to do at least 5 past paper questions in each topic