Chem - ATP Notes
Look for the number of marks before answering the question
Sometimes a straightforward question might expect more than one point to be made
Be specific with volumes and solution names (name acids and alkalis used)
Even if you can make a generalised statement
Cracking of Long Chain alkanes
Alkane and Catalyst → Heated
Initially → Air passes through
More accurate
Burette → Variable volumes
Volumetric pipettes → Measure fixed volume
Lesser data → Poorer graph (2 marks)
pH 1 - 3
Slow to add → Reaction begins while adding
When larger beaker is used → Printed text - visible faster - less depth
Repeat and compare
Adv → More accurate; Dis.adv. → Takes longer/ slower
Hydrated substance ↑
OBSERVATION →
not "soluble in excess"
Speak about heat → Speak about temperature
Usage of polystyrene cup
Whenever dissolving is concerned
Air hole fully open
Compare → Quantitative description
In which solvent is solute more solvent in?
Rate of rxn. → Mass loss
Error → Tubing from flask should go into Con. Sulfuric Acid and tubing to gas jar → Not in acid
General
Flame test →
CO → Limewater → Milky
Residue → Wash and dry
2
Heating hydrated Chromium (III) Nitrate → Gives off oxygen
Adding in excess → Can be test
Disadvantage of burette → Slow/ takes more time/ can overshoot the required volume
Experiment Design
Reactions → State in which container → Beaker/ flask/ test-tube
Control variables (How would you make it a fair test) → AT LEAST 3
Dependent variable → How would you measure
STIR AND MIX
Read question → Check what the question asks
Jabez notes