Input interpretation
mercury dipotassium tetrathiocyanate | molar mass
Result
Find the molar mass, M, for mercury dipotassium tetrathiocyanate: 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_4HgK_2N_4S_4 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i C (carbon) | 4 Hg (mercury) | 1 K (potassium) | 2 N (nitrogen) | 4 S (sulfur) | 4 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) | 4 | 12.011 Hg (mercury) | 1 | 200.592 K (potassium) | 2 | 39.0983 N (nitrogen) | 4 | 14.007 S (sulfur) | 4 | 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) C (carbon) | 4 | 12.011 | 4 × 12.011 = 48.044 Hg (mercury) | 1 | 200.592 | 1 × 200.592 = 200.592 K (potassium) | 2 | 39.0983 | 2 × 39.0983 = 78.1966 N (nitrogen) | 4 | 14.007 | 4 × 14.007 = 56.028 S (sulfur) | 4 | 32.06 | 4 × 32.06 = 128.24 M = 48.044 g/mol + 200.592 g/mol + 78.1966 g/mol + 56.028 g/mol + 128.24 g/mol = 511.10 g/mol
Unit conversion
0.5111 kg/mol (kilograms per mole)
Comparisons
≈ 0.71 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 2.6 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 8.7 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 8.5×10^-22 grams | 8.5×10^-25 kg (kilograms) | 511 u (unified atomic mass units) | 511 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 511