Input interpretation
![lithium bis(trimethylsilyl)amide | molar mass](../image_source/13501e8b95559c381c8b9408df40368c.png)
lithium bis(trimethylsilyl)amide | molar mass
Result
![Find the molar mass, M, for lithium bis(trimethylsilyl)amide: 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: [(CH_3)_3Si]_2NLi Use the chemical formula to count the number of atoms, N_i, for each element: | N_i C (carbon) | 6 H (hydrogen) | 18 Li (lithium) | 1 N (nitrogen) | 1 Si (silicon) | 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) | 6 | 12.011 H (hydrogen) | 18 | 1.008 Li (lithium) | 1 | 6.94 N (nitrogen) | 1 | 14.007 Si (silicon) | 2 | 28.085 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) | 6 | 12.011 | 6 × 12.011 = 72.066 H (hydrogen) | 18 | 1.008 | 18 × 1.008 = 18.144 Li (lithium) | 1 | 6.94 | 1 × 6.94 = 6.94 N (nitrogen) | 1 | 14.007 | 1 × 14.007 = 14.007 Si (silicon) | 2 | 28.085 | 2 × 28.085 = 56.170 M = 72.066 g/mol + 18.144 g/mol + 6.94 g/mol + 14.007 g/mol + 56.170 g/mol = 167.33 g/mol](../image_source/1c6a1a22f51475611aa20e920e05a6fb.png)
Find the molar mass, M, for lithium bis(trimethylsilyl)amide: 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: [(CH_3)_3Si]_2NLi Use the chemical formula to count the number of atoms, N_i, for each element: | N_i C (carbon) | 6 H (hydrogen) | 18 Li (lithium) | 1 N (nitrogen) | 1 Si (silicon) | 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) | 6 | 12.011 H (hydrogen) | 18 | 1.008 Li (lithium) | 1 | 6.94 N (nitrogen) | 1 | 14.007 Si (silicon) | 2 | 28.085 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) | 6 | 12.011 | 6 × 12.011 = 72.066 H (hydrogen) | 18 | 1.008 | 18 × 1.008 = 18.144 Li (lithium) | 1 | 6.94 | 1 × 6.94 = 6.94 N (nitrogen) | 1 | 14.007 | 1 × 14.007 = 14.007 Si (silicon) | 2 | 28.085 | 2 × 28.085 = 56.170 M = 72.066 g/mol + 18.144 g/mol + 6.94 g/mol + 14.007 g/mol + 56.170 g/mol = 167.33 g/mol
Unit conversion
![0.1673 kg/mol (kilograms per mole)](../image_source/24cbeb068d3a2da5b22ac0c32f4a0f33.png)
0.1673 kg/mol (kilograms per mole)
Comparisons
![≈ ( 0.23 ≈ 1/4 ) × molar mass of fullerene ( ≈ 721 g/mol )](../image_source/009583da7480316a4659224a4141b8dd.png)
≈ ( 0.23 ≈ 1/4 ) × molar mass of fullerene ( ≈ 721 g/mol )
![≈ 0.86 × molar mass of caffeine ( ≈ 194 g/mol )](../image_source/5f416c23f0cf3cdd29c7c2f1fbbb5860.png)
≈ 0.86 × molar mass of caffeine ( ≈ 194 g/mol )
![≈ 2.9 × molar mass of sodium chloride ( ≈ 58 g/mol )](../image_source/8a6f4490456f86687b903a720d3ff079.png)
≈ 2.9 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
![Mass of a molecule m from m = M/N_A: | 2.8×10^-22 grams | 2.8×10^-25 kg (kilograms) | 167 u (unified atomic mass units) | 167 Da (daltons)](../image_source/3c42fc767a9e14746a03b3142592e088.png)
Mass of a molecule m from m = M/N_A: | 2.8×10^-22 grams | 2.8×10^-25 kg (kilograms) | 167 u (unified atomic mass units) | 167 Da (daltons)
![Relative molecular mass M_r from M_r = M_u/M: | 167](../image_source/c3323c37d3867ea915d9b710d10ecb0e.png)
Relative molecular mass M_r from M_r = M_u/M: | 167