Altering the Amount of Heat Produced When Magnesium Reacts with Sulphuric Acid

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Altering the Amount of Heat Produced When Magnesium Reacts with Sulphuric Acid

When energy in the form of heat is given out of a reaction it is an

exothermic reaction. Exothermic reactions usually need activation

energy, the energy to break the bonds in the chemicals and to start

the reaction. Once the bonds are broken new stronger bonds are formed.

In an exothermic reaction energy in the form so heat is given out to

the surrounding when the products are formed. Therefore there is an

average rise in temperature; energy is lost which results in a

negative ?H.

The outcome variable for this experiment is to conclude what changes

can be made to vary the heat energy when magnesium is reacted with

sulphuric acid.

Magnesium + Sulphuric Acid ¡ú Magnesium Sulphate + Hydrogen

Mg (s) + H2SO4 (a) ¡ú MgSO4 (a) + H2 (g)

There are many variables which can be changed in some way to effect

the reaction, some of which are listed below:-

Volume of Sulphuric Acid

Concentration of Sulphuric Acid

Initial temperature of Sulphuric Acid

Motion of liquid (speed of stirring)

Amount and size of magnesium

Purity of magnesium

The extent of oxidation on the surface of the magnesium

Addition of Catalysts

Size of Container

Temperature of surrounding environment

Pressure at which reaction is conducted

Insulation of the test-tube

Height of thermometer above the base of the test-tube

Explaining variables

In solutions of higher concentration, particles are closer together.

They have a greater chance of colliding. Because there are more

collisions the reaction rate is greater.

How does temperature affect the rate of a chem...

... middle of paper ...

...by encasing each

experiment to prevent any changes in temperature at the start of the

reaction to the end of the reaction from affecting the experiment.

Extensions to the investigation

Computers could be used to carry out data logs of the temperature

during the experiment to give a more reliable and more accurate

account of the experiments and to help distinguish patterns between

concentration, heat produced and rate of reaction throughout each

reaction.

More concentrations of acid could be used to see if they also have

similar affects on the temperature rise.

Different substances could be reacted to see if they behave similarly.

More repeats could be carried out to qualify the findings. These could

be done under different conditions to see how the reactions react

under a colder or hotter environment.

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