The Rate of Reaction of Metals With Acid

Increasing temperature is also the affect the rate of equation. When the temperature increase, gas molecules increases their energy and shifts the energy distribution curve to the right.

Activation energy is the minimum energy with which particles need to collide to cause a reaction. It is measured in kj mol-1. In the experiment, the reaction between powdered Magnesium and a solution of hydrochloride acid. Magnesium chloride and hydrogen gas are formed. The temperature of both mixtures is the same. The higher concentration of acid has the effect of increasing the number of collisions between particles that can react with each other. So, the number of collisions that reach the activation energy also increases. The initial rate of the reaction is much faster in many reactions where concentration reagents are used. A graph can plot by the Arrhenius equation: ln k = constant - EA (1/T) / R where k is the rate constant of the reaction. R is the gas constant, 8.31 J K-1 mol-1 and T is the temperature in kelvins.

Planning

The experiment is about a range of acids react with magnesium and the kinetics of the reactions can be investigated. Hydrochloride is monobasic and very strong acid, which the pH value is about 1. The equation is Mg(s) + 2HCl(aq) › MgCl2(aq) + H2(g). Hydrochloride acid causes burn and irritating the respiratory system. Measuring cylinders are used to measure the volume of hydrochloride. I need to read the bottom line of the level to make sure the volume is precisely. The control variables are the room temperature and the pressure. The variable is the volume of the hydrochloride acid.

Implementing

Goggles should be wear all the time when doing experiments. A white gas is produced by the experiment, which is poisonous for the health. The results are repeated and take the mean value. Surrounding temperature should not be having a big difference when each experiment carries out.

HCl (1M)/cm3

Mg/(g)

Initial Temperature/?

Final Temperature/?

Run 1

4

0.503

20

34

Run 2

6

0.503

9

43

Run 3

6

0.503

20

58

Concluding and evaluating

When the volume of hydrochloride acid increases, the temperature rise up quickly whiles the magnesium powder keep constant. The differences between the initial temperature and the final temperature are also big. This means that Mg react with acid vigorously.

Temperature might not be read accurately because it is hard to read the highest temperature. It might be drop slightly since the surrounding temperature lower than the reaction temperature.