Input interpretation
manganese(II) nitrate | molecular mass
Result
Find the molecular mass, m, for manganese(II) nitrate: 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: Mn(NO_3)_2 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i Mn (manganese) | 1 N (nitrogen) | 2 O (oxygen) | 6 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 Mn (manganese) | 1 | 54.938044 N (nitrogen) | 2 | 14.007 O (oxygen) | 6 | 15.999 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 Mn (manganese) | 1 | 54.938044 | 1 × 54.938044 = 54.938044 N (nitrogen) | 2 | 14.007 | 2 × 14.007 = 28.014 O (oxygen) | 6 | 15.999 | 6 × 15.999 = 95.994 m = 54.938044 u + 28.014 u + 95.994 u = 178.946 u
Unit conversions
178.95 Da (daltons)
0.17895 kDa (kilodaltons)
2.9715×10^-22 grams
2.9715×10^-25 kg (kilograms)
178.95 chemical atomic mass units (unit officially deprecated)
179 physical atomic mass units (unit officially deprecated)
Comparisons as mass of molecule
≈ ( 0.25 ≈ 1/4 ) × molecular mass of fullerene ( ≈ 721 u )
≈ 0.92 × molecular mass of caffeine ( ≈ 194 u )
≈ 3.1 × molecular mass of sodium chloride ( ≈ 58 u )
Corresponding quantities
Relative atomic mass A_r from A_r = m_aN_A/M_u: | 179
Molar mass M from M = m_aN_A: | 179 g/mol (grams per mole)
Relative molecular mass M_r from M_r = m_mN_A/M_u: | 179
Molar mass M from M = m_mN_A: | 179 g/mol (grams per mole)