Input interpretation
barium dithionate dihydrate | molar mass
Result
Find the molar mass, M, for barium dithionate dihydrate: 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: BaS_2O_6·2H_2O Use the chemical formula to count the number of atoms, N_i, for each element: | N_i Ba (barium) | 1 H (hydrogen) | 4 O (oxygen) | 8 S (sulfur) | 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) Ba (barium) | 1 | 137.327 H (hydrogen) | 4 | 1.008 O (oxygen) | 8 | 15.999 S (sulfur) | 2 | 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) Ba (barium) | 1 | 137.327 | 1 × 137.327 = 137.327 H (hydrogen) | 4 | 1.008 | 4 × 1.008 = 4.032 O (oxygen) | 8 | 15.999 | 8 × 15.999 = 127.992 S (sulfur) | 2 | 32.06 | 2 × 32.06 = 64.12 M = 137.327 g/mol + 4.032 g/mol + 127.992 g/mol + 64.12 g/mol = 333.47 g/mol
Unit conversion
0.33347 kg/mol (kilograms per mole)
Comparisons
≈ 0.46 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 1.7 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 5.7 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 5.5×10^-22 grams | 5.5×10^-25 kg (kilograms) | 333 u (unified atomic mass units) | 333 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 333