Input interpretation
![potassium phthalimide | molar mass](../image_source/7a3a1c9d3f091b9ae5a7b24b3d60f0a1.png)
potassium phthalimide | molar mass
Result
![Find the molar mass, M, for potassium phthalimide: 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: C_8H_4KNO_2 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i C (carbon) | 8 H (hydrogen) | 4 K (potassium) | 1 N (nitrogen) | 1 O (oxygen) | 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) C (carbon) | 8 | 12.011 H (hydrogen) | 4 | 1.008 K (potassium) | 1 | 39.0983 N (nitrogen) | 1 | 14.007 O (oxygen) | 2 | 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) C (carbon) | 8 | 12.011 | 8 × 12.011 = 96.088 H (hydrogen) | 4 | 1.008 | 4 × 1.008 = 4.032 K (potassium) | 1 | 39.0983 | 1 × 39.0983 = 39.0983 N (nitrogen) | 1 | 14.007 | 1 × 14.007 = 14.007 O (oxygen) | 2 | 15.999 | 2 × 15.999 = 31.998 M = 96.088 g/mol + 4.032 g/mol + 39.0983 g/mol + 14.007 g/mol + 31.998 g/mol = 185.223 g/mol](../image_source/a6fbea65a62465a84a7f2f5044e229f0.png)
Find the molar mass, M, for potassium phthalimide: 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: C_8H_4KNO_2 Use the chemical formula to count the number of atoms, N_i, for each element: | N_i C (carbon) | 8 H (hydrogen) | 4 K (potassium) | 1 N (nitrogen) | 1 O (oxygen) | 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) C (carbon) | 8 | 12.011 H (hydrogen) | 4 | 1.008 K (potassium) | 1 | 39.0983 N (nitrogen) | 1 | 14.007 O (oxygen) | 2 | 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) C (carbon) | 8 | 12.011 | 8 × 12.011 = 96.088 H (hydrogen) | 4 | 1.008 | 4 × 1.008 = 4.032 K (potassium) | 1 | 39.0983 | 1 × 39.0983 = 39.0983 N (nitrogen) | 1 | 14.007 | 1 × 14.007 = 14.007 O (oxygen) | 2 | 15.999 | 2 × 15.999 = 31.998 M = 96.088 g/mol + 4.032 g/mol + 39.0983 g/mol + 14.007 g/mol + 31.998 g/mol = 185.223 g/mol
Unit conversion
![0.18522 kg/mol (kilograms per mole)](../image_source/ba792145cb5b7fd409e4402a67e092dd.png)
0.18522 kg/mol (kilograms per mole)
Comparisons
![≈ 0.26 × molar mass of fullerene ( ≈ 721 g/mol )](../image_source/f5a9e34802618a78140170b63a5d1f3c.png)
≈ 0.26 × molar mass of fullerene ( ≈ 721 g/mol )
![≈ 0.95 × molar mass of caffeine ( ≈ 194 g/mol )](../image_source/6154cab4dd9e840fe342908356169898.png)
≈ 0.95 × molar mass of caffeine ( ≈ 194 g/mol )
![≈ 3.2 × molar mass of sodium chloride ( ≈ 58 g/mol )](../image_source/378e4e2556373c5986b50e760c69bded.png)
≈ 3.2 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
![Mass of a molecule m from m = M/N_A: | 3.1×10^-22 grams | 3.1×10^-25 kg (kilograms) | 185 u (unified atomic mass units) | 185 Da (daltons)](../image_source/53fad2013b016155ab4b996dc2aa62d5.png)
Mass of a molecule m from m = M/N_A: | 3.1×10^-22 grams | 3.1×10^-25 kg (kilograms) | 185 u (unified atomic mass units) | 185 Da (daltons)
![Relative molecular mass M_r from M_r = M_u/M: | 185](../image_source/1f350583a11cbbfb1cfbf9f6ec0973f0.png)
Relative molecular mass M_r from M_r = M_u/M: | 185