Question

Argue whether this chemical reaction supports or does not support the Law of Conservation of Matter.

Make sure to explain and justify your answer.



A researcher combines 28g of Magnesium and 15g of Oxygen.

The mass of the substances after the chemical reaction is 32g.

Answer 1

Step-by-step explanation:

The reaction is as follows:

2Mg(s) + O2(g) ---> 2MgO(s)

and the researcher said that 32 g of MgO was produced.

Stoichiometry:

28 g Mg × (1 mol Mg/24.305 g Mg) = 1.15 mol Mg

15 g O2 × (1 mol O2/15.999 g O2) = 0.938 mol O2

1.15 mol Mg × (2 mol MgO/2 mol MgO) = 1.15 mol MgO

1.15 mol MgO × (40.3044 g MgO/1 mol MgO) = 46.6 g MgO

0.938 mol O2 × (2 mol MgO/1 mol O2) = 1.88 mol MgO

1.88 mol MgO × (40.3044 g MgO/1 mol MgO = 75.6 g MgO

Based on these numbers, the amount of product after the reaction is much less than expected so these results don't seem to support the law of conservation of matter.