ISA Flashcards
(42 cards)
What is the independent variable?
The conc. of iodide ions.
What is the rate equation?
Rate=k[A]^m[B]^n
What does the order of reaction mean?
0- [A] changes and rate stays the same
1- Rate is proportional to [A]
2- Rate is proportional to [A]^2
What doe a bigger rate constant mean?
faster rate of reaction
When is k the same?
For a particular reaction at a particular temperature
What does increasing the temperature of a reaction do?
Increases rate of reaction because number of collisions increases, as well as the energy of each collision.
Conc. of reactants and orders of reaction stay the same so k must increase for rate equation to balance.
RATE OF REACTION
The change in the amount of reactants or products per unit of time
How do you work out gradient?
change in y/change in x
What is gradient?
order of reaction
What is the rate determining step?
Slowest step in a multi step reaction.
If a reactant occurs in the rate equation, it must affect the rate.
How do you work out % yield?
actual yield/theoretical yield X 100
How do you work out theoretical yield?
Moles of reactant to moles of desired product (ratio)
What is a variable?
Quantity that has the potential to change.
DISCRETE DATA
Counting (eg bubbles)
CONTINUOUS
any value in a scale
What are scatter plots good for?
Showing how two sets of data are related.
VALID RESULTS
Answer original question, fair test
ACCURATE RESULTS
Close to true value
PRECISE
Using sensitive instruments that measure in small increments
RELIABLE
Consistently reproduced.
Why is ethanoic anhydride over ethanoyl chloride?
Cheaper,
Safer as do not get HCl gas produced
HCl(g) dissolves in water and becomes corrosive.
Reacts more slowly
What is Carbon NMR?
Tells you how many different carbon environments a molecule has.
Describe NMR
Any atomic nucleus with an odd number of nucleons in its nucleus has a nuclear spin. This causes a weak magnetic field.
NMR spectroscopy looks at how small magnetic field reacts when you put in a much larger external magnetic field.
Where do sources of error come from (from experiment)?
- Glasswear error
- Not done under standard conditions - temperature fluctuations prevented by being in a thermostatically controlled water bath
- Timing error- longer time stirring is more accurate.