Input interpretation
ethylmercuric cysteine | molar mass
Result
Find the molar mass, M, for ethylmercuric cysteine: 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_5H_11HgNO_2S Use the chemical formula, C_5H_11HgNO_2S, to count the number of atoms, N_i, for each element: | N_i C (carbon) | 5 H (hydrogen) | 11 Hg (mercury) | 1 N (nitrogen) | 1 O (oxygen) | 2 S (sulfur) | 1 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) | 5 | 12.011 H (hydrogen) | 11 | 1.008 Hg (mercury) | 1 | 200.592 N (nitrogen) | 1 | 14.007 O (oxygen) | 2 | 15.999 S (sulfur) | 1 | 32.06 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) | 5 | 12.011 | 5 × 12.011 = 60.055 H (hydrogen) | 11 | 1.008 | 11 × 1.008 = 11.088 Hg (mercury) | 1 | 200.592 | 1 × 200.592 = 200.592 N (nitrogen) | 1 | 14.007 | 1 × 14.007 = 14.007 O (oxygen) | 2 | 15.999 | 2 × 15.999 = 31.998 S (sulfur) | 1 | 32.06 | 1 × 32.06 = 32.06 M = 60.055 g/mol + 11.088 g/mol + 200.592 g/mol + 14.007 g/mol + 31.998 g/mol + 32.06 g/mol = 349.80 g/mol
Unit conversion
0.3498 kg/mol (kilograms per mole)
Comparisons
≈ 0.49 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 1.8 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 6 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 5.8×10^-22 grams | 5.8×10^-25 kg (kilograms) | 350 u (unified atomic mass units) | 350 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 350