Input interpretation
potassium hexafluoroarsenate(V) | molar mass
Result
Find the molar mass, M, for potassium hexafluoroarsenate(V): 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: KAsF_6 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i As (arsenic) | 1 F (fluorine) | 6 K (potassium) | 1 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) As (arsenic) | 1 | 74.921595 F (fluorine) | 6 | 18.998403163 K (potassium) | 1 | 39.0983 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) As (arsenic) | 1 | 74.921595 | 1 × 74.921595 = 74.921595 F (fluorine) | 6 | 18.998403163 | 6 × 18.998403163 = 113.990418978 K (potassium) | 1 | 39.0983 | 1 × 39.0983 = 39.0983 M = 74.921595 g/mol + 113.990418978 g/mol + 39.0983 g/mol = 228.0103 g/mol
Unit conversion
0.2280103 kg/mol (kilograms per mole)
Comparisons
≈ 0.32 × 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) | 228 u (unified atomic mass units) | 228 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 228