Input interpretation
![beryllium oxide | molar mass](../image_source/c0a125d09f88f67c6535d5b90e2ba26f.png)
beryllium oxide | molar mass
Result
![Find the molar mass, M, for beryllium oxide: 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: BeO Use the chemical formula to count the number of atoms, N_i, for each element: | N_i Be (beryllium) | 1 O (oxygen) | 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) Be (beryllium) | 1 | 9.0121831 O (oxygen) | 1 | 15.999 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) Be (beryllium) | 1 | 9.0121831 | 1 × 9.0121831 = 9.0121831 O (oxygen) | 1 | 15.999 | 1 × 15.999 = 15.999 M = 9.0121831 g/mol + 15.999 g/mol = 25.011 g/mol](../image_source/8d7d123fa08e8fa670d355435bd2645f.png)
Find the molar mass, M, for beryllium oxide: 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: BeO Use the chemical formula to count the number of atoms, N_i, for each element: | N_i Be (beryllium) | 1 O (oxygen) | 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) Be (beryllium) | 1 | 9.0121831 O (oxygen) | 1 | 15.999 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) Be (beryllium) | 1 | 9.0121831 | 1 × 9.0121831 = 9.0121831 O (oxygen) | 1 | 15.999 | 1 × 15.999 = 15.999 M = 9.0121831 g/mol + 15.999 g/mol = 25.011 g/mol
Unit conversion
![0.025011 kg/mol (kilograms per mole)](../image_source/3c24428a00ada1a7d350b62f8f782d19.png)
0.025011 kg/mol (kilograms per mole)
Comparisons
![≈ ( 0.13 ≈ 1/8 ) × molar mass of caffeine ( ≈ 194 g/mol )](../image_source/1fab4f1be32d4239ee85295c34b8c832.png)
≈ ( 0.13 ≈ 1/8 ) × molar mass of caffeine ( ≈ 194 g/mol )
![≈ 0.43 × molar mass of sodium chloride ( ≈ 58 g/mol )](../image_source/f7b0ef6b9dc017e9fa743a2cd0b9db59.png)
≈ 0.43 × molar mass of sodium chloride ( ≈ 58 g/mol )
![≈ 1.4 × molar mass of water ( ≈ 18 g/mol )](../image_source/a73b1c677738a02c278fcd0300bf2cf7.png)
≈ 1.4 × molar mass of water ( ≈ 18 g/mol )
Corresponding quantities
![Mass of a molecule m from m = M/N_A: | 4.2×10^-23 grams | 4.2×10^-26 kg (kilograms) | 25 u (unified atomic mass units) | 25 Da (daltons)](../image_source/b341b6e697d597fca84502f440f4aa58.png)
Mass of a molecule m from m = M/N_A: | 4.2×10^-23 grams | 4.2×10^-26 kg (kilograms) | 25 u (unified atomic mass units) | 25 Da (daltons)
![Relative molecular mass M_r from M_r = M_u/M: | 25](../image_source/decd138a65b4dc5c4dc4089e50aba9d6.png)
Relative molecular mass M_r from M_r = M_u/M: | 25