Input interpretation
antimony(III) sulfide | molar mass
Result
Find the molar mass, M, for antimony(III) sulfide: 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: Sb_2S_3 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i S (sulfur) | 3 Sb (antimony) | 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) S (sulfur) | 3 | 32.06 Sb (antimony) | 2 | 121.760 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) S (sulfur) | 3 | 32.06 | 3 × 32.06 = 96.18 Sb (antimony) | 2 | 121.760 | 2 × 121.760 = 243.520 M = 96.18 g/mol + 243.520 g/mol = 339.70 g/mol
Unit conversion
0.3397 kg/mol (kilograms per mole)
Comparisons
≈ 0.47 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 1.7 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 5.8 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 5.6×10^-22 grams | 5.6×10^-25 kg (kilograms) | 340 u (unified atomic mass units) | 340 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 340