rates of reaction

Question 1

what are the four ways that we can increase the rate of a reaction?

Answer 1

surface area
temperature
concentration
presence of a catalyst

Question 2

what is a variable?

Answer 2

a factor that can affect the results of an experiment

Question 3

what is an independent variable?

Answer 3

the part of your experiment that you change. Y AXIS

Question 4

what is a dependent variable?

Answer 4

the part of your experiment you are measuring. X AXIS

Question 5

what is a control variable?

Answer 5

the things you have changed in an experiment but you need to keep the same

Question 6

what is the collision theory?

Answer 6

particles must collide in order to react with eachother

Question 7

what is the experiment to test the effect of surface area?

Answer 7

marble chips and hydrochloric acid.

CaCO3
calcium carbonate + hydrochloric acid = calcium chloride + water

Question 8

how do we know when a reaction is finished?

Answer 8

the line levels out and becomes horizontal

Question 9

what is the experiment to test the effect of concentration?

Answer 9

hydrochloric acid + magnesium = magnesium chloride + hydrogen

2HCl + Mg = MgCl + H2

Question 10

what is the experiment to test the effect of temperature?

Answer 10

heated up sodium thiosulphate and hydrochloric acid to see if the pencil cross disappeared

Question 11

what is the word equation for our test on the effect of temperature?

Answer 11

sodium thiosulphate + hydrochloric acid = (arrow) sodium chloride + water + sulphur dioxide + sulphur

Question 12

what is the experiment to test the effect of catalysts?

Answer 12

hydrogen peroxide (arrow) water + oxygen

2H(2)O(2) (Arrow) 2H(2)O + O(2)

Question 13

what is the activation energy?

Answer 13

the minimum amount of energy needed to start a reaction. if the activation energy is not met, there will be no reaction

Question 14

how can we visually see how fast a rate of reaction occurs from the products produced?

Answer 14

colour change

gas formation

Question 15

what is the effect of concentration on the rate of reaction?

Answer 15

when you have a HIGHER CONCENTRATION there are more articles which means MORE COLLISIONS

Question 16

what is the effect of temperature on the rate of reaction?

Answer 16

when particles are heated they gain KINETIC ENERGY. this means that particles will collide more often and also they have more energy and so the activation energy is achieved more frequently

Question 17

what is the effect of catalysts on the rate of reaction?

Answer 17

when a catalyst is involved in a reaction, they dont change neither itself or the products. catalysts lower the activation energy by offering an alternative route for the reaction

Question 18

what is the effect of surface area on the rate of reaction?

Answer 18

the smaller the chips the larger the surface area. this allows more collisions at the surface which results in the increase in the rate of reaction