Input interpretation
cerium(III) sulfate hydrate | molar mass
Result
Find the molar mass, M, for cerium(III) sulfate hydrate: 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: Ce_2(SO_4)_3·xH_2O Use the chemical formula to count the number of atoms, N_i, for each element: | N_i Ce (cerium) | 2 H (hydrogen) | 16 O (oxygen) | 20 S (sulfur) | 3 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) Ce (cerium) | 2 | 140.116 H (hydrogen) | 16 | 1.008 O (oxygen) | 20 | 15.999 S (sulfur) | 3 | 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) Ce (cerium) | 2 | 140.116 | 2 × 140.116 = 280.232 H (hydrogen) | 16 | 1.008 | 16 × 1.008 = 16.128 O (oxygen) | 20 | 15.999 | 20 × 15.999 = 319.980 S (sulfur) | 3 | 32.06 | 3 × 32.06 = 96.18 M = 280.232 g/mol + 16.128 g/mol + 319.980 g/mol + 96.18 g/mol = 712.52 g/mol
Unit conversion
0.7125 kg/mol (kilograms per mole)
Comparisons
≈ 0.99 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 3.7 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 12 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 1.2×10^-21 grams | 1.2×10^-24 kg (kilograms) | 713 u (unified atomic mass units) | 713 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 713