What number of aluminum atoms are in a 65.8g sample of Aluminum Oxide?
Al2O3.
mols Al2O3 = grams/molar mass = ?
Since there are two Al atoms in a molecule of Al2O3, twice that will be mols Al.
Then remember that 1 mol of Al contains 5.02E23 atoms Al.
To determine the number of aluminum atoms in a sample of aluminum oxide, we need to use the concept of moles and Avogadro's number.
1. Find the molar mass of aluminum oxide (Al2O3):
- Aluminum has an atomic mass of 26.98 g/mol.
- Oxygen has an atomic mass of 16.00 g/mol.
- Since there are two aluminum atoms and three oxygen atoms in aluminum oxide, the molar mass of Al2O3 is:
(2 * 26.98 g/mol) + (3 * 16.00 g/mol) = 101.96 g/mol
2. Calculate the number of moles in the sample:
- Divide the mass of the sample by the molar mass of aluminum oxide:
65.8 g / 101.96 g/mol = 0.645 moles
3. Use Avogadro's number to find the number of aluminum atoms:
- Avogadro's number is approximately 6.022 x 10^23 molecules per mole.
- Since there are two aluminum atoms per molecule of Al2O3, multiply the number of moles by 2:
0.645 moles * 2 * 6.022 x 10^23 atoms/mol = 7.78 x 10^23 aluminum atoms
Therefore, there are approximately 7.78 x 10^23 aluminum atoms in a 65.8g sample of aluminum oxide.
To determine the number of aluminum atoms present in a sample of Aluminum Oxide, you will need to follow these steps:
Step 1: Identify the molar mass of Aluminum Oxide (Al₂O₃).
- The molar mass of Aluminum (Al) is 26.98 g/mol.
- The molar mass of Oxygen (O) is 16.00 g/mol.
- Aluminum Oxide consists of two Aluminum atoms and three Oxygen atoms, so the molar mass of Aluminum Oxide is:
(2 * molar mass of Aluminum) + (3 * molar mass of Oxygen)
Step 2: Calculate the number of moles of Aluminum Oxide.
- To do this, divide the mass of the sample by its molar mass:
Moles = mass (g) / molar mass (g/mol)
Step 3: Determine the number of moles of Aluminum.
- Since each formula unit of Aluminum Oxide has two Aluminum atoms, the moles of Aluminum will be:
Moles of Aluminum = (moles of Aluminum Oxide) * 2
Step 4: Calculate the number of Aluminum atoms.
- Multiply the moles of Aluminum by Avogadro's number (6.022 x 10^23) to obtain the number of Aluminum atoms.
Now, let's apply this method to the given sample:
Step 1: The molar mass of Aluminum Oxide is:
(2 * 26.98 g/mol) + (3 * 16.00 g/mol) = 101.96 g/mol
Step 2: The number of moles of Aluminum Oxide is:
Moles = 65.8 g / 101.96 g/mol = 0.645 moles (rounded to three decimal places)
Step 3: The number of moles of Aluminum is:
Moles of Aluminum = 0.645 moles * 2 = 1.29 moles
Step 4: The number of Aluminum atoms is:
Number of Aluminum atoms = 1.29 moles * (6.022 x 10^23 atoms/mol) = 7.77 x 10^23 Aluminum atoms
Therefore, there are approximately 7.77 x 10^23 Aluminum atoms in a 65.8g sample of Aluminum Oxide.