The aim of this practical is to observe the difference in the reactivity between Mg and Ca when hot and cold water is added.
We think they will react in some kind of form.
The independent variable was the temperature of the water and also the quantity of metal use in the experiment and the dependent variable was the reaction.
* Mg (s)
* Ca (s)
* Cold and hot water
* Test tubes with rack
1. The Magnesium was cleaned with sandpaper.
2. Two pieces of magnesium was put into two test tubes and two pieces of calcium was put into two test tubes.
3. Cold water was added into two test tubes one with calcium one with magnesium.
4. Two droplets of phenolphalein were added in each of the test tubes filled with cold water to observe the change in ph.
5. Water was heated over a Benson burner and poured into the two test tubes without water while observing the reactions.
6. Two droplets of phenolphalein were added in each of the test tubes filled with cold water to observe the change in ph.
Relative reactivity of
There was a minimum reaction. Fig. 1
There is a bigger reaction than with the cold water. Fig. 2
The temperature of the water increases right away. Before we dropped the phenolphthalein the solution was white, fig.3, but after adding the phenolphthalein it turned pink, fig.4, which means that the reaction is basic.
The temperature stayed the same but because the water was hot the reaction was more explosive and quicker. Before the phenolphthalein the solution was white, fig.3, and after dropping the phenolphthalein it turned pink, fig.4, which means that is a basic solution.
Are your results in accordance with what you have learned about reactivity?
Yes because calcium has more orbits the atom has the less energy it needs to give away electrons. In this case the atom that has more orbits is the calcium that is why it reacts more than the magnesium because calcium needs less energy to give electrons away. And the magnesium didn’t react much because it needs more energy that the one that we gave it.
Write the balanced equation for the reaction between Mg and H2O:
Mg (s) + H2O (l) MgO (s) + H2 (g)
Other element might have been present.
The hot water might have been heated more.
We learned that both magnesium and calcium is basic solutions because of the pink tint to the color. We also learned that calcium reacted faster than magnesium.