what are the molecular or formula masses of each of the following compounds,al[oh]3,hno3,pcl3,cuco3,feso4
To calculate the molecular or formula mass of a compound, you need to calculate the sum of the atomic masses of all the atoms in the compound.
1. Aluminum hydroxide (Al[OH]3):
To calculate the molecular mass of Al[OH]3, first determine the atomic masses of the elements involved:
- Aluminum (Al) has an atomic mass of 26.98 g/mol.
- Oxygen (O) has an atomic mass of 16.00 g/mol.
- Hydrogen (H) has an atomic mass of 1.01 g/mol.
Next, count the number of atoms of each element in the compound:
- Al: 1 atom
- O: 3 atoms
- H: 3 atoms
Finally, multiply the atomic mass of each element by the number of atoms and sum them up to get the molecular mass:
(1 × 26.98) + (3 × 16.00) + (3 × 1.01) = 78.00 g/mol
Therefore, the molecular mass of Al[OH]3 is 78.00 g/mol.
2. Nitric acid (HNO3):
To calculate the molecular mass of HNO3, consider the atomic masses of the elements involved:
- Hydrogen (H) has an atomic mass of 1.01 g/mol.
- Nitrogen (N) has an atomic mass of 14.01 g/mol.
- Oxygen (O) has an atomic mass of 16.00 g/mol.
Count the number of atoms of each element in the compound:
- H: 1 atom
- N: 1 atom
- O: 3 atoms
Multiply the atomic mass of each element by the number of atoms and sum them up:
(1 × 1.01) + (1 × 14.01) + (3 × 16.00) = 63.01 g/mol
Thus, the molecular mass of HNO3 is 63.01 g/mol.
3. Phosphorus trichloride (PCl3):
To calculate the molecular mass of PCl3, consider the atomic masses of the elements involved:
- Phosphorus (P) has an atomic mass of 30.97 g/mol.
- Chlorine (Cl) has an atomic mass of 35.45 g/mol.
Count the number of atoms of each element in the compound:
- P: 1 atom
- Cl: 3 atoms
Multiply the atomic mass of each element by the number of atoms and sum them up:
(1 × 30.97) + (3 × 35.45) = 137.32 g/mol
Therefore, the molecular mass of PCl3 is 137.32 g/mol.
4. Copper carbonate (CuCO3):
To calculate the formula mass of CuCO3, consider the atomic masses of the elements involved:
- Copper (Cu) has an atomic mass of 63.55 g/mol.
- Carbon (C) has an atomic mass of 12.01 g/mol.
- Oxygen (O) has an atomic mass of 16.00 g/mol.
Count the number of atoms of each element in the compound:
- Cu: 1 atom
- C: 1 atom
- O: 3 atoms
Multiply the atomic mass of each element by the number of atoms and sum them up:
(1 × 63.55) + (1 × 12.01) + (3 × 16.00) = 123.55 g/mol
Thus, the molecular mass of CuCO3 is 123.55 g/mol.
5. Iron(II) sulfate (FeSO4):
To calculate the formula mass of FeSO4, consider the atomic masses of the elements involved:
- Iron (Fe) has an atomic mass of 55.85 g/mol.
- Sulfur (S) has an atomic mass of 32.07 g/mol.
- Oxygen (O) has an atomic mass of 16.00 g/mol.
Count the number of atoms of each element in the compound:
- Fe: 1 atom
- S: 1 atom
- O: 4 atoms
Multiply the atomic mass of each element by the number of atoms and sum them up:
(1 × 55.85) + (1 × 32.07) + (4 × 16.00) = 151.91 g/mol
Hence, the molecular mass of FeSO4 is 151.91 g/mol.