Input interpretation
N-hexadecane | molar mass
Result
Find the molar mass, M, for N-hexadecane: 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: CH_3(CH_2)_14CH_3 Use the chemical formula, CH_3(CH_2)_14CH_3, to count the number of atoms, N_i, for each element: | N_i C (carbon) | 16 H (hydrogen) | 34 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) | 16 | 12.011 H (hydrogen) | 34 | 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) C (carbon) | 16 | 12.011 | 16 × 12.011 = 192.176 H (hydrogen) | 34 | 1.008 | 34 × 1.008 = 34.272 M = 192.176 g/mol + 34.272 g/mol = 226.448 g/mol
Unit conversion
0.22645 kg/mol (kilograms per mole)
Comparisons
≈ 0.31 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 1.2 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 3.9 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 3.8×10^-22 grams | 3.8×10^-25 kg (kilograms) | 226 u (unified atomic mass units) | 226 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 226