Group Members:· Luke· Molly· Ellis · Taylor Aim:To investigate how theconcentration of the reactant will affect the reaction rate of Magnesium metal+ Hydrochloric acid à Magnesium chloride + Hydrogen.
Introduction: A chemical reaction is aprocess in which two or more substances collide with each other and combine toform a new substance (Paul M. Treichl, 2017). Rate of reaction is the speed at which thechemical reaction at which it occurs (Laidler, 2017). For example, a lowreaction rate means that the molecules are combining at a slower speed. TheParticle Theory or other wise known as Kinetic Molecular Theory addresses thenature of the particles and how they behave.
“Thekinetic theory of matter (particle theory) says that all matter consists ofmany, very small particles which are constantly moving or in a continual stateof motion. The degree to which the particles move is determined by the amountof energy they have and their relationship to other particles” (University of Leicester, 2000). The rateof reaction is affected by factors like temperature, concentration, surfacearea and catalysts, all these can bemanipulated to speed up chemical reactions. The temperature affects the rate ofthe reactions as the heat causes the molecules to speed up and move faster,that in turn increases the rate of which the reaction occurs. For example,baking a cake in the oven (Chem4kids, 2017).
Increasing ordecreasing the concentration of a substance changes the strength which can alsospeed up or slow down a chemical reaction. The higher the concentration themore particles, this means that there is a higher probability of a collision,for example when you add more octane to gasoline it will burn with moreefficiency (Chem4kids, 2017). Changing thesurface area of a substance is another effective way to increase the reactionrate. For example, if you were to cut up a block into small pieces you would beexposing more of its surfaces which means that the reactant (acid) would thenbe able to reach more of the objects surfaces and react better. This works asthe more surfaces that are exposed the more particles there are to react withthe other particles allowing more collisions to take place (Clark, 2002).
The last factorthat can control the reaction rate is a catalyst. A catalyst is a substancethat lowers the required activation energy which by doing so increases thereaction rate. The activation energy is the amount of energy which is needed toform a reaction for example the petrol needed to start a fire.
Catalyst allowsreactants to from products without actually being consumed. The enzymes in yourbody are natural catalysts that react but don’t consume too much of your energyan example of this is when you digest food. (Chemistry 302, ND) In the experiment we will investigate how changingthe concentration of the reactant will change the reaction rate.
The reactionwhich we have chosen to investigate is the Magnesium metal + Hydrochloric acid à Magnesium chloride + Hydrogen. Justified Hypothesis: As the concentration isincreased, the reaction rate increases because there is an increased number ofparticles which means there is a more likely chance for an increase ofmeaningful collisions. Materials: · Retort stand /clamp· Large glass dish· Measuringcylinder x2· Tubing · Stopper· Conical flask x3· Magnesium 9×1 cmpieces · Hydrochloric acid0.5M, 1M,1.5M x 15ml each· Stopwatch· Balance scales · Spatula Diagram Figure one