Finding the Formula of a Metal Oxide through Experimentation

The video tutorial explains how to determine the formula of a metal oxide using experimental methods. It focuses on the oxidation of magnesium, detailing the process of weighing magnesium, heating it in a crucible, and calculating the resulting magnesium oxide's mass. The tutorial demonstrates how to calculate the empirical formula by converting masses to moles and determining the ratio of magnesium to oxygen. The empirical formula of magnesium oxide is found to be MgO, and the video concludes with a summary of the steps involved in the experiment.

What are the two methods mentioned for determining the formula of a metal oxide?

• Reacting metal with water and measuring the gas produced

• Dissolving the metal in acid and measuring the pH change

• Heating the metal in a vacuum and measuring the residue

• Forming the metal oxide from the metal and reducing the metal oxide to form the metal

Why is the crucible lid placed slightly ajar during the magnesium oxidation experiment?

• To cool the reaction faster

• To let moisture in

• To prevent magnesium oxide from escaping and allow oxygen to enter

• To allow heat to escape

What is the purpose of heating the magnesium ribbon in the crucible?

• To melt the magnesium

• To evaporate impurities

• To react magnesium with oxygen to form magnesium oxide

• To change the color of magnesium

How is the mass of oxygen involved in the reaction calculated?

• By multiplying the mass of magnesium by the atomic mass of oxygen

• By adding the mass of magnesium and magnesium oxide

• By subtracting the mass of magnesium from the mass of magnesium oxide

• By dividing the mass of magnesium oxide by the mass of magnesium

What is the empirical formula of magnesium oxide based on the experimental results?

• Mg3O2

• MgO

• Mg2O

• MgO2

What is the relative atomic mass of magnesium used in the calculations?

• 16

• 12

• 24

• 32

What is the final step in determining the formula of a metal oxide experimentally?

• Cooling the metal oxide

• Heating the metal oxide

• Weighing the metal oxide

• Calculating the empirical formula from the number of moles