Chemistry C6 Flashcards
How do you find the rate of reaction from a particular point on a graph?
Use a tangent,
- follow from the point you want to measure
- draw a dot on the line
- use ruler to draw tangent
- draw a triangle to the tangent(bigger=better)
- then use equation for the gradient
What’s the equation for the gradient of a graph?
Gradient= change in y over change in x
or
Gradient= up over across
How can you follow a reaction?
- loss of mass
- production of gas
- colour change
How do you measure the gas coming off of an experiment?
- measuring syringe
- inverted measuring cylinder
Problems with using a inverted measuring cylinder?
- gas is already present
- gas is lost before the bung is placed
Which have faster reaction times?
1) a)low temp
b) high temp
2) a)lump
b) powder
3) a) low concentration
b) high concentration
1) B
2) B
3) B
Collision theory- temperature
Whats’s the difference between Low temp and High temp?
Low temp
-slow movement, not much energy
-when they collide some react and some don’t
High temp
-high speed, lots of energy
-when they collide there are lots of reactions
Collision theory- temperature
Conclusion…
The higher the temperature the higher the rate of reaction will be. This is because the particles have more energy, so they can move around faster. Leading to more successful collisions.
Collision theory- surface area
Lump vs Powder
In the lump there is less surface area so less space to react.
In the powder they are more spread out so there is more available space to react.
Collision theory- surface area
Conclusion…
The larger the surface area, the faster the rate of reaction, this is because there are more particles available to react, leading to more successful collisions.
Collision theory- pressure/concentration
Low vs high concentration
High concentration menas particles are more likely to bump into each other.
Collision theory- pressure/concentration
Conclusion…
The higher the pressure/concentration, the aster the rate of reaction will be, this is because there are more particles in a fixed volume so there is a higher chance of a successful collision.
Collision theory- catalyst
none vs catalyst
Faster with catalyst as particles attach to the catalyst so that the other particles can react with them easier
Le chatelier’s principle
if you change the conditions of a reversible reaction at equilibrium the system will try counteract the change
Equilibrium
A state in which opposing forces are balanced
