Input interpretation
![rhodium(III) oxide hydrate | molar mass](../image_source/e5948cba8cb9917ea12d842d723bad06.png)
rhodium(III) oxide hydrate | molar mass
Result
![Find the molar mass, M, for rhodium(III) oxide hydrate: 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: Rh_2O_3·xH_2O Use the chemical formula, Rh_2O_3·xH_2O, to count the number of atoms, N_i, for each element: | N_i H (hydrogen) | 2 O (oxygen) | 4 Rh (rhodium) | 2 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) H (hydrogen) | 2 | 1.008 O (oxygen) | 4 | 15.999 Rh (rhodium) | 2 | 102.90550 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) H (hydrogen) | 2 | 1.008 | 2 × 1.008 = 2.016 O (oxygen) | 4 | 15.999 | 4 × 15.999 = 63.996 Rh (rhodium) | 2 | 102.90550 | 2 × 102.90550 = 205.81100 M = 2.016 g/mol + 63.996 g/mol + 205.81100 g/mol = 271.823 g/mol](../image_source/9839a5651195d8b43b5009c1362bd967.png)
Find the molar mass, M, for rhodium(III) oxide hydrate: 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: Rh_2O_3·xH_2O Use the chemical formula, Rh_2O_3·xH_2O, to count the number of atoms, N_i, for each element: | N_i H (hydrogen) | 2 O (oxygen) | 4 Rh (rhodium) | 2 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) H (hydrogen) | 2 | 1.008 O (oxygen) | 4 | 15.999 Rh (rhodium) | 2 | 102.90550 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) H (hydrogen) | 2 | 1.008 | 2 × 1.008 = 2.016 O (oxygen) | 4 | 15.999 | 4 × 15.999 = 63.996 Rh (rhodium) | 2 | 102.90550 | 2 × 102.90550 = 205.81100 M = 2.016 g/mol + 63.996 g/mol + 205.81100 g/mol = 271.823 g/mol
Unit conversion
![0.271823 kg/mol (kilograms per mole)](../image_source/9725b10723efff75c597e848d83d3439.png)
0.271823 kg/mol (kilograms per mole)
Comparisons
![≈ 0.38 × molar mass of fullerene ( ≈ 721 g/mol )](../image_source/7990151db727a8f4ba573ea705357b1c.png)
≈ 0.38 × molar mass of fullerene ( ≈ 721 g/mol )
![≈ 1.4 × molar mass of caffeine ( ≈ 194 g/mol )](../image_source/ebc81c181d1dc2f393ce89fe58fbe440.png)
≈ 1.4 × molar mass of caffeine ( ≈ 194 g/mol )
![≈ 4.7 × molar mass of sodium chloride ( ≈ 58 g/mol )](../image_source/a67cfea6bb47b17af5c0d4d3bb031e87.png)
≈ 4.7 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
![Mass of a molecule m from m = M/N_A: | 4.5×10^-22 grams | 4.5×10^-25 kg (kilograms) | 272 u (unified atomic mass units) | 272 Da (daltons)](../image_source/d4353ae87af065f1b966d8f58b1c152f.png)
Mass of a molecule m from m = M/N_A: | 4.5×10^-22 grams | 4.5×10^-25 kg (kilograms) | 272 u (unified atomic mass units) | 272 Da (daltons)
![Relative molecular mass M_r from M_r = M_u/M: | 272](../image_source/739dc7f4c9bc546ce919266e4c89a395.png)
Relative molecular mass M_r from M_r = M_u/M: | 272