Input interpretation
![promethium(III) fluoride | molar mass](../image_source/b202d126619f0c7dbc343a3abc026c81.png)
promethium(III) fluoride | molar mass
Result
![Find the molar mass, M, for promethium(III) fluoride: 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: PmF_3 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i F (fluorine) | 3 Pm (promethium) | 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) F (fluorine) | 3 | 18.998403163 Pm (promethium) | 1 | 145 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) F (fluorine) | 3 | 18.998403163 | 3 × 18.998403163 = 56.995209489 Pm (promethium) | 1 | 145 | 1 × 145 = 145 M = 56.995209489 g/mol + 145 g/mol = 202 g/mol](../image_source/5e1296429ee004358e0158c3a988ac6c.png)
Find the molar mass, M, for promethium(III) fluoride: 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: PmF_3 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i F (fluorine) | 3 Pm (promethium) | 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) F (fluorine) | 3 | 18.998403163 Pm (promethium) | 1 | 145 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) F (fluorine) | 3 | 18.998403163 | 3 × 18.998403163 = 56.995209489 Pm (promethium) | 1 | 145 | 1 × 145 = 145 M = 56.995209489 g/mol + 145 g/mol = 202 g/mol
Unit conversion
![0.202 kg/mol (kilograms per mole)](../image_source/349842aaa95e7d7532f7980138bbbe77.png)
0.202 kg/mol (kilograms per mole)
Comparisons
![≈ 0.28 × molar mass of fullerene ( ≈ 721 g/mol )](../image_source/c4786653d514821231a272322ac335f2.png)
≈ 0.28 × molar mass of fullerene ( ≈ 721 g/mol )
![≈ molar mass of caffeine ( ≈ 194 g/mol )](../image_source/89aba9b57aa762f3b09a6c261d08ec29.png)
≈ molar mass of caffeine ( ≈ 194 g/mol )
![≈ 3.5 × molar mass of sodium chloride ( ≈ 58 g/mol )](../image_source/06e9b6b658d7ca055138bd80844a35f3.png)
≈ 3.5 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
![Mass of a molecule m from m = M/N_A: | 3.4×10^-22 grams | 3.4×10^-25 kg (kilograms) | 202 u (unified atomic mass units) | 202 Da (daltons)](../image_source/6109d0816e5b05ca79c58c29e9ba8baa.png)
Mass of a molecule m from m = M/N_A: | 3.4×10^-22 grams | 3.4×10^-25 kg (kilograms) | 202 u (unified atomic mass units) | 202 Da (daltons)
![Relative molecular mass M_r from M_r = M_u/M: | 202](../image_source/849bdc3de77fdde13248e19de0572da2.png)
Relative molecular mass M_r from M_r = M_u/M: | 202