the major commercial aluminium ore is bauxite,AlO3.H2O(s).What is its molar mass?The analysis of a representive sample of bauxite shows it contains 70% by mass of Al2O3..What is the maximum mass of aluminium metal that could be obtained from 200kg of bauxite by the HAll electrolytic process?
look up the atomic masses in your periodic table. Add up the appropriate multiples to get the molecular molar mass.
The rest is just algebra, if you know the yield of the Hall process.
To find the molar mass of bauxite (AlO3.H2O), you need to calculate the total mass of each individual element in the compound:
1. Molar mass of Al (aluminium) = 26.98 g/mol
2. Molar mass of O (oxygen) = 16.00 g/mol
3. Molar mass of H (hydrogen) = 1.01 g/mol
Now, let's calculate the molar mass of AlO3.H2O:
1. Multiply the molar mass of Al by the number of Al atoms in the compound: 26.98 g/mol x 1 = 26.98 g/mol
2. Multiply the molar mass of O by the number of O atoms in the compound: 16.00 g/mol x 3 = 48.00 g/mol
3. Multiply the molar mass of H by the number of H atoms in the compound: 1.01 g/mol x 2 = 2.02 g/mol
Next, calculate the sum of these masses:
26.98 g/mol + 48.00 g/mol + 2.02 g/mol = 77.00 g/mol
Therefore, the molar mass of bauxite (AlO3.H2O) is 77.00 g/mol.
Now, let's calculate the maximum mass of aluminium metal that could be obtained from 200 kg of bauxite using the Hall electrolytic process:
1. Determine the mass percentage of Al2O3 in bauxite: If bauxite contains 70% by mass of Al2O3, then you have 200 kg x (70/100) = 140 kg of Al2O3.
2. Calculate the molar mass of Al2O3:
- Molar mass of Al = 26.98 g/mol
- Molar mass of O = 16.00 g/mol
Therefore, the molar mass of Al2O3 = (26.98 g/mol x 2) + (16.00 g/mol x 3) = 101.96 g/mol.
3. Convert the mass of Al2O3 to moles:
- Moles of Al2O3 = Mass of Al2O3 / Molar mass of Al2O3
- Moles of Al2O3 = 140,000 g / 101.96 g/mol = 1,371.30 mol.
4. Based on the balanced equation for the Hall electrolytic process, you know that for every 2 moles of Al2O3, you get 4 moles of Al.
Therefore, Moles of Al = (1,371.30 mol Al2O3 / 2 mol Al2O3) x 4 mol Al = 2,742.60 mol Al.
5. Finally, to find the maximum mass of aluminium, multiply the moles of Al by the molar mass of Al:
- Mass of Al = Moles of Al x Molar mass of Al
- Mass of Al = 2,742.60 mol x 26.98 g/mol = 74,056.47 g.
So, the maximum mass of aluminium metal that could be obtained from 200 kg of bauxite using the Hall electrolytic process is approximately 74,056.47 grams or 74.06 kg.