Acids & Alkalis, Solubility

AIM

I want to find out how the concentration of Hydrochloric acid affects the amount of hydrogen or the time it takes to produce 30cm3 of gas, when the Hydrochloric acid reacts with the magnesium powder.

Prediction

I predict that the amount of hydrogen in the measuring cylinder will increase as the concentration increases; this is because if there is more concentration there shall be more particles for the magnesium to collide with so the reaction will be faster. I think that my prediction is true because if you increase the concentration there are more particles in the test tube so there is more likely to be a collision and when a collision happens there is a reaction and hydrogen is produced. I plan to take 5 readings and repeat one more time to be able get an average. I predict the time it takes the hydrogen to reach 30cm3 will range from 5s to 25s. I think that the reaction will happen like this Magnesium +Hydrochloric acid > Magnesium Chloride + Hydrogen

Mg(s) + 2HCL(aq) > Mgcl2(aq) + H2(g)

Diagram

Measuring cylinder

Test tube Hydrogen Pipe

Bung

Hydrochloric Acid

Magnesium powder

...

This is a preview of the whole essay

Mg(s) + 2HCL(aq) > Mgcl2(aq) + H2(g)

Diagram

Measuring cylinder

Test tube Hydrogen Pipe

Bung

Hydrochloric Acid

Magnesium powder

Tub with Water

Fair Test

To keep this a fair test the things I am keeping the same are, the amount of magnesium powder, the same amount of liquid in the test tube before I put the magnesium powder in, the same amount of gas I am going to measure, the same bung, the same clock, the same measuring cylinder and the same tub. The variable I am going to change is the Hydrochloric acid to water ratio. I have to make sure that I use the same mass of magnesium, this is because it will make it a fair test and the results will be related to each other, otherwise the results will be completely different to what I expect and it will be, and it will ruin the experiment.

Plan

Get all items- Test tube, magnesium powder, hydrochloric acid, tub filled with water, bung, clock, measuring cylinder and pipe.

Fill the measuring cylinder with water and place over tub making sure that there no gas in measuring cylinder. Put 5cm of hydrochloric acid in test tube.

Put one end of the pipe in the tub and the other end over the side of the test tube. Put the bung on immediately after the 0.10g of magnesium powder is put in.

Measure the amount of time that it tares till the hydrogen reaches 30cm3 and record it in the table.

Repeat experiment with 4cm Hydrochloric Acid and 1cm Water, 3cm Hydrochloric Acid and 2cm Water, 2cm Hydrochloric Acid and 3cm Water and 1cm Hydrochloric Acid and 4cm Water.

Results Table

Analysis

I would say that my results are of good quality and are quite accurate. The pattern found in the results was that the higher the amount concentration the faster the hydrogen reaches the point and this proves my prediction. In my results there was an anomalous point which was because I did not put the bung on quickly enough so it took longer time for the gas to reach 30cm3.

Evaluation

I would say that my results are pretty reliable and of good quality because I have taken 2 sets of results and averaged them to make the graph.

I could improve my results by making sure that I put the bung on at the right exact moment so I get the right results. I think that the lat result was too high because I might have accidentally put more magnesium or more hydrochloric acid.