Input interpretation
barium iron oxide | molar mass
Result
Find the molar mass, M, for barium iron oxide: M = sum _iN_im_i Plan: • Write the chemical formula and gather atomic masses from the periodic table. • Determine values for N_i and m_i using these items. • Finally, compute the mass. Write the chemical formula: BaFe_12O_19 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i Ba (barium) | 1 Fe (iron) | 12 O (oxygen) | 19 Look up the atomic mass, m_i, in g·mol^(-1) for each element in the periodic table: | N_i | m_i/g·mol^(-1) Ba (barium) | 1 | 137.327 Fe (iron) | 12 | 55.845 O (oxygen) | 19 | 15.999 Multiply N_i by m_i to compute the mass for each element. Then sum those values to compute the molar mass, M: Answer: | | | N_i | m_i/g·mol^(-1) | mass/g·mol^(-1) Ba (barium) | 1 | 137.327 | 1 × 137.327 = 137.327 Fe (iron) | 12 | 55.845 | 12 × 55.845 = 670.140 O (oxygen) | 19 | 15.999 | 19 × 15.999 = 303.981 M = 137.327 g/mol + 670.140 g/mol + 303.981 g/mol = 1111.448 g/mol
Unit conversion
1.1114 kg/mol (kilograms per mole)
Comparisons
≈ 1.5 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 5.7 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 19 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 1.8×10^-21 grams | 1.8×10^-24 kg (kilograms) | 1111 u (unified atomic mass units) | 1.1 kDa (kilodaltons)
Relative molecular mass M_r from M_r = M_u/M: | 1111