Input interpretation
2, 3, 7, 8, 12, 13, 17, 18-octaethyl-21H, 23 H-porphine magnesium(II) | molar mass
Result
Find the molar mass, M, for 2, 3, 7, 8, 12, 13, 17, 18-octaethyl-21H, 23 H-porphine magnesium(II): 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_36H_46MgN_4)^2+ Use the chemical formula to count the number of atoms, N_i, for each element: | N_i Mg (magnesium) | 1 C (carbon) | 36 N (nitrogen) | 4 H (hydrogen) | 46 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) Mg (magnesium) | 1 | 24.305 C (carbon) | 36 | 12.011 N (nitrogen) | 4 | 14.007 H (hydrogen) | 46 | 1.008 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) Mg (magnesium) | 1 | 24.305 | 1 × 24.305 = 24.305 C (carbon) | 36 | 12.011 | 36 × 12.011 = 432.396 N (nitrogen) | 4 | 14.007 | 4 × 14.007 = 56.028 H (hydrogen) | 46 | 1.008 | 46 × 1.008 = 46.368 M = 24.305 g/mol + 432.396 g/mol + 56.028 g/mol + 46.368 g/mol = 559.097 g/mol
Unit conversion
0.5591 kg/mol (kilograms per mole)
Comparisons
≈ 0.78 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 2.9 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 9.6 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 9.3×10^-22 grams | 9.3×10^-25 kg (kilograms) | 559 u (unified atomic mass units) | 559 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 559