Input interpretation
aluminum chloride | molecular mass
Result
Find the molecular mass, m, for aluminum chloride: 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: AlCl_3 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i Al (aluminum) | 1 Cl (chlorine) | 3 Look up the atomic mass, m_i, in unified atomic mass units, u, for each element in the periodic table: | N_i | m_i/u Al (aluminum) | 1 | 26.9815385 Cl (chlorine) | 3 | 35.45 Multiply N_i by m_i to compute the mass for each element. Then sum those values to compute the molecular mass, m: Answer: | | | N_i | m_i/u | mass/u Al (aluminum) | 1 | 26.9815385 | 1 × 26.9815385 = 26.9815385 Cl (chlorine) | 3 | 35.45 | 3 × 35.45 = 106.35 m = 26.9815385 u + 106.35 u = 133.33 u
Unit conversions
133.3 Da (daltons)
0.1333 kDa (kilodaltons)
2.214×10^-22 grams
2.214×10^-25 kg (kilograms)
133.3 chemical atomic mass units (unit officially deprecated)
133.4 physical atomic mass units (unit officially deprecated)
Comparisons as mass of molecule
≈ ( 0.19 ≈ 1/5 ) × molecular mass of fullerene ( ≈ 721 u )
≈ 0.69 × molecular mass of caffeine ( ≈ 194 u )
≈ 2.3 × molecular mass of sodium chloride ( ≈ 58 u )
Corresponding quantities
Relative atomic mass A_r from A_r = m_aN_A/M_u: | 133
Molar mass M from M = m_aN_A: | 133 g/mol (grams per mole)
Relative molecular mass M_r from M_r = m_mN_A/M_u: | 133
Molar mass M from M = m_mN_A: | 133 g/mol (grams per mole)