How do you calculate the molar mass of compounds using the provided atomic masses?
To calculate the molar mass of compounds, you need to sum together the atomic masses of all the atoms present in the compound. This involves multiplying the atomic mass of each element by the number of atoms of that element in the compound and then adding all the results together.
Explanation:
Molar Mass Calculation: The molar mass of a compound is the sum of the atomic masses of all the atoms in the compound. This can be calculated using the provided atomic masses for each element and the number of atoms of each element in the compound.
Example with H3PO4:
For H3PO4, we have 3 atoms of hydrogen (H), 1 atom of phosphorus (P), and 4 atoms of oxygen (O). By substituting the atomic masses provided (H=0.998, O=15.998, P=30.974) into the formula (3 x H) + P + (4 x O), we can calculate the molar mass as follows:
(3 x 0.998) + 30.974 + (4 x 15.998) = 98.0 g/mol
Calculation for K2Cr2O4:
Similarly, for K2Cr2O4, there are 2 atoms of potassium (K), 2 atoms of chromium (Cr), and 4 atoms of oxygen (O). Using the atomic masses provided (K=39.098, O=15.998, Cr=51.996) in the formula (2 x K) + (2 x Cr) + (4 x O), we find the molar mass as:
(2 x 39.098) + (2 x 51.996) + (4 x 15.998) = 194.2 g/mol
Calculation for HClO4:
For HClO4, there is 1 atom of hydrogen (H), 1 atom of chlorine (Cl), and 4 atoms of oxygen (O). Using the provided atomic masses (H=0.998, O=15.998, Cl=35.453) in the formula (1 x H) + (1 x Cl) + (4 x O), we get the molar mass as:
(1 x 0.998) + 35.453 + (4 x 15.998) = 100.5 g/mol
Calculation for AlCl3:
Finally, for AlCl3, there is 1 atom of aluminum (Al) and 3 atoms of chlorine (Cl). Substituting the atomic masses (Al=26.9815, Cl=35.453) into the formula Al + (3 x Cl), we find the molar mass as:
26.9815 + (3 x 35.453) = 133.4 g/mol
By following these calculations, you can determine the molar mass of various compounds based on the provided atomic masses for each element.