RATE of REACTION?

Question

ok guys, how does surface area, temperature, and a catalyst effect rate of reaction--please help!!

Answer 1

Surface area
The bigger surface area,the bigger chance for the collision to happen.Thus the probability for the sucessful collision to happen also will increase.Therefore,rate of reaction is proportional to surface area.

Temperature
An increase in temperature will increase the kinetic energy of molecules.This will result more collisions between the reactant and the substance and more successful conversion of the substance into product.So,the rate of reaction will increase.

Catalyst
When a chemical reaction take place,bonds in the reacting molecules need to be broken and then new bonds form in the products.so,all reactions begin with the breaking of bonds,and the energy to fo this is called activation energy.Catalyst work by lowering the activation energy for the reaction which they catalyse.So reaction will happen easier because not much energy required.Therefore,the positive catalyst will increase the rate of reaction while the negative catalyst will decrease the rate of reaction.

Hope this will help..Good luck!!=)

Answer 2

All three factors can increase the rate of reaction.

If there is a greater surface area, then there are most exposed molecules to take part in the chemical reaction, so the rate gets increased.

Increasing the temperature makes the molecules move around more quickly, so that also increases the rate of the reaction.

And a catalyst--BY DEFINITION--is something that speeds up a chemical reaction.

Answer 3

large Surface area decreases the rate of reaction. High temperature increases the rate of reaction. Catalyst increases the rate of reaction by lowering the activation energy.

Answer 4

surface area increases the rate of reaction as there is more space to react.
temperature can either increase or decrease the rate depending on the reaction. like formation of ammonia needs low temperature and high pressure.
catalyst also increases or decreases the rate depending on the catalyst. like in fridge, the catalyst is used to decrease the rate of decomposition. and some are necessary for the reaction to take place. like chlorophyll in plants to convert sun light,water, CO2 into carbohydrates.

Answer 5

All of them accelerate the reaction:
A reaction happens when the reacting molecules have enough energy (above the energy of activation) and collide with the proper orientation.

Increasing the surface area increases the number of molecules which collide with each other and therefore increases the number of effective collisions.

Increasing temperature means increasing the energy of the molecules. Thus more molecules are above the activation energy limit and the reaction occurs faster.

Catalysts reduce the energy of activation. Thus more molecules at a given temperature will have enough energy to react.

Answer 6

Surface area: in how many places can a reaction between two phases occur? Also, surface shape: crystal lattices get weaker the less uniform crystal there is, therefore ions or molecules in dendritic crystals (like snowflakes) will be less restrained to interact with the solvent or reagents.

Temperature: determines the energy exchange between educts and products (thermodynamically), thereby the potential pushing the reaction into its course, and also excites molecules or atoms into more reactive states. Quite often the wrong parts of molecules, too...

Catalysts help the educts to get into a more reactive state, ideally preparing them to start reacting without any more incentives (such as hydrogen/air mixtures above finely dispersed platinum, a snob chemist's cigarette lighter).

Answer 7

the more the surface area the higher the rate, the higher the temperature tha higher the rate, and the presence of a catalyst reduces the activation energy hence the rate is raised

Answer 8

increasing surface area and catalyst both increases rate of reaction.
increasing temperature may increase or decrease rate of reaction depending on reaction is endothermic or exothermic respectively.

Answer 9

all three increase the rate.