Input interpretation
7α-hydroxycholest-4-en-3-one | molar mass
Result
Find the molar mass, M, for 7α-hydroxycholest-4-en-3-one: 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_27H_44O_2 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i C (carbon) | 27 H (hydrogen) | 44 O (oxygen) | 2 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) | 27 | 12.011 H (hydrogen) | 44 | 1.008 O (oxygen) | 2 | 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) | 27 | 12.011 | 27 × 12.011 = 324.297 H (hydrogen) | 44 | 1.008 | 44 × 1.008 = 44.352 O (oxygen) | 2 | 15.999 | 2 × 15.999 = 31.998 M = 324.297 g/mol + 44.352 g/mol + 31.998 g/mol = 400.647 g/mol
Unit conversion
0.40065 kg/mol (kilograms per mole)
Comparisons
≈ 0.56 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 2.1 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 6.9 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 6.7×10^-22 grams | 6.7×10^-25 kg (kilograms) | 401 u (unified atomic mass units) | 401 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 401