Input interpretation
2, 3, 7, 8, 12, 13, 17, 18-octaethyl-21H, 23 H-porphine iron(III) acetate | molar mass
Result
Find the molar mass, M, for 2, 3, 7, 8, 12, 13, 17, 18-octaethyl-21H, 23 H-porphine iron(III) acetate: 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: C_38H_47FeN_4O_2 Use the chemical formula, C_38H_47FeN_4O_2, to count the number of atoms, N_i, for each element: | N_i C (carbon) | 42 Fe (iron) | 1 H (hydrogen) | 55 N (nitrogen) | 4 O (oxygen) | 6 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) C (carbon) | 42 | 12.011 Fe (iron) | 1 | 55.845 H (hydrogen) | 55 | 1.008 N (nitrogen) | 4 | 14.007 O (oxygen) | 6 | 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) C (carbon) | 42 | 12.011 | 42 × 12.011 = 504.462 Fe (iron) | 1 | 55.845 | 1 × 55.845 = 55.845 H (hydrogen) | 55 | 1.008 | 55 × 1.008 = 55.440 N (nitrogen) | 4 | 14.007 | 4 × 14.007 = 56.028 O (oxygen) | 6 | 15.999 | 6 × 15.999 = 95.994 M = 504.462 g/mol + 55.845 g/mol + 55.440 g/mol + 56.028 g/mol + 95.994 g/mol = 767.769 g/mol
Unit conversion
0.7678 kg/mol (kilograms per mole)
Comparisons
≈ 1.1 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 4 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 13 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 1.3×10^-21 grams | 1.3×10^-24 kg (kilograms) | 768 u (unified atomic mass units) | 768 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 768