Rate of rate of hydrochloric acid and mangesium ribbon

... short then I will have to do the opposite and increase the length of magnesium that I use. The optimum rate that I am trying to find is a reaction that isn't too short but isn't too long, so I can get enough results to plot a good graph. I need to find the optimum volume of hydrochloric acid so that it is in excess after the reaction is over.

Apart from trying to find the optimum rate of reaction I also have to find out how to keep the temperature change down. This is because as the reaction is taking place the temperature will rise because the reaction is exothermic, and this could cause my results to be inaccurate as the temperature change will heat up the acid and give the acid particles more energy so they will move faster and collide with the magnesium with greater force causing more successful collisions per second.

To show that the hydrogen gas is not being given of from the water in the hydrochloric acid I will have to conduct a control experiment. This is when I will react magnesium ribbon with distilled water to show that there is no reaction between magnesium ribbon and water and that the hydrogen gas is evolving from the hydrochloric acid when it is being broken down into magnesium chloride and hydrogen.

Preliminary results

After my preliminary experiments I discovered that if I used 50cm3 of hydrochloric acid with 3 cm of magnesium ribbon then I could obtain some good results.

Also with these quantities the temperature change is kept to a minimum

Time (seconds) 5 10 15

Gas evolved for 1M hydrochloric acid (cm3) 4 7 11

Gas evolved for 2M hydrochloric acid (cm3) 18 24 24

Starting temperature (oC) End temperature (oC) Temperature change (oC)

22 25 3

As these results produced a reasonable volume of gas in a reasonable time these were the quantities of chemicals that I used.

I also used these quantities of chemicals because it kept the temperature increase to a minimum.

Method

1. Put on safety goggles

2. Collect clamp stand, clamp and boss

3. Collect conical flask and measuring cylinder

4. Collect stop clock

5. Measure out 50 cm3 of 0.0M hydrochloric acid with the measuring cylinder

6. Pour hydrochloric acid into the conical flask

7. Collect thermometer

8. Measure the starting temperature of the hydrochloric acid

9. Measure 3cm of magnesium ribbon

10. Clean the surface of the magnesium with the sandpaper

11. Drop the magnesium into the conical flask

12. Q ...