Input interpretation
zinc phosphate | molar mass
Result
Find the molar mass, M, for zinc phosphate: 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: Zn_3(PO_4)_2 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i O (oxygen) | 8 P (phosphorus) | 2 Zn (zinc) | 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) O (oxygen) | 8 | 15.999 P (phosphorus) | 2 | 30.973761998 Zn (zinc) | 3 | 65.38 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) O (oxygen) | 8 | 15.999 | 8 × 15.999 = 127.992 P (phosphorus) | 2 | 30.973761998 | 2 × 30.973761998 = 61.947523996 Zn (zinc) | 3 | 65.38 | 3 × 65.38 = 196.14 M = 127.992 g/mol + 61.947523996 g/mol + 196.14 g/mol = 386.08 g/mol
Unit conversion
0.3861 kg/mol (kilograms per mole)
Comparisons
≈ 0.54 × molar mass of fullerene ( ≈ 721 g/mol )
≈ 2 × molar mass of caffeine ( ≈ 194 g/mol )
≈ 6.6 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
Mass of a molecule m from m = M/N_A: | 6.4×10^-22 grams | 6.4×10^-25 kg (kilograms) | 386 u (unified atomic mass units) | 386 Da (daltons)
Relative molecular mass M_r from M_r = M_u/M: | 386