Flashcards
Rates of reaction
Cards in this deck (15)
- 1What does the rate of reaction depend on?1. The surface area or size of the particles
2. the concentration of the solutions
3. the temperature
4. the presence of catalyst - 2How do you calculate the rate of reaction from time?rate (s-1) = 1
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time taken for metal to disappear - 3How can you tell when a reaction has finished?Gas: reading the time when the mass/ gas volume first reaches optimum
timing the reaction until you see the production of gas has stopped.
Solid: time until no more can be seen - 4What is activation energy?the minimum energy needed by colliding particles to react.
- 5What happens to particles at higher temperatures?1. They have more energy and move faster
2. they collide more often
3. leads to more successful collisions
4. this increases the rate of reaction. - 6What happens to particles at higher concentration of solution?1. there are more present I the same volume
2. they collide more often
3. leads to more successful collisions
4. this increases the rate of reaction. - 7what happens when a catalyst is present at higher temperatures when all the other factors are kept the same?1. the gas volume starts at 0
2. The gas volume is higher every time
3. The line on the graph levels off earlier
4. but ends as the same final gas volume - 8what's the equation for a metal reacting with a dilute acid?Mg+2HCL -> MGCL2 + H2
- 9what's the equation for a marble chips reacting with a dilute hydrochloric acid?CaCO3 + 2HCL -> CaCL2 + H2O + CO2
- 10what's the equation for the catalyst decomposition of hydrogen peroxide?2H2O2 -> 2H2O + O2
- 11What is a catalyst?A substance which speeds up the rate of reaction without being used up. It reduces the activation energy and creates more successful collisions.
- 12How will the mass change?It will stay the same as the catalyst is not used up
- 13What is the catalyst for the decomposition of hydrogen peroxide?Manganese (IV) oxide, MnO2
- 14What is the catalyst for the contact process (sulfuric acid manufacture)?Vanadium (V) oxide, V2O5
- 15What is the catalyst for the Haber process (ammonia manufacture)?Iron