Input interpretation
![strontium bromide hexahydrate | molar mass](../image_source/dbb7418b920bdd45379e9dca68313f2d.png)
strontium bromide hexahydrate | molar mass
Result
![Find the molar mass, M, for strontium bromide hexahydrate: 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: SrBr_2·6H_2O Use the chemical formula, SrBr_2·6H_2O, to count the number of atoms, N_i, for each element: | N_i Br (bromine) | 2 H (hydrogen) | 2 O (oxygen) | 1 Sr (strontium) | 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) Br (bromine) | 2 | 79.904 H (hydrogen) | 2 | 1.008 O (oxygen) | 1 | 15.999 Sr (strontium) | 1 | 87.62 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) Br (bromine) | 2 | 79.904 | 2 × 79.904 = 159.808 H (hydrogen) | 2 | 1.008 | 2 × 1.008 = 2.016 O (oxygen) | 1 | 15.999 | 1 × 15.999 = 15.999 Sr (strontium) | 1 | 87.62 | 1 × 87.62 = 87.62 M = 159.808 g/mol + 2.016 g/mol + 15.999 g/mol + 87.62 g/mol = 265.44 g/mol](../image_source/7d60ef582b76b8690e2e82569e136eff.png)
Find the molar mass, M, for strontium bromide hexahydrate: 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: SrBr_2·6H_2O Use the chemical formula, SrBr_2·6H_2O, to count the number of atoms, N_i, for each element: | N_i Br (bromine) | 2 H (hydrogen) | 2 O (oxygen) | 1 Sr (strontium) | 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) Br (bromine) | 2 | 79.904 H (hydrogen) | 2 | 1.008 O (oxygen) | 1 | 15.999 Sr (strontium) | 1 | 87.62 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) Br (bromine) | 2 | 79.904 | 2 × 79.904 = 159.808 H (hydrogen) | 2 | 1.008 | 2 × 1.008 = 2.016 O (oxygen) | 1 | 15.999 | 1 × 15.999 = 15.999 Sr (strontium) | 1 | 87.62 | 1 × 87.62 = 87.62 M = 159.808 g/mol + 2.016 g/mol + 15.999 g/mol + 87.62 g/mol = 265.44 g/mol
Unit conversion
![0.2654 kg/mol (kilograms per mole)](../image_source/925496a38e58ad3698402c5c20fb8803.png)
0.2654 kg/mol (kilograms per mole)
Comparisons
![≈ 0.37 × molar mass of fullerene ( ≈ 721 g/mol )](../image_source/497ff4bb63f016693c4527ff5b97bab4.png)
≈ 0.37 × molar mass of fullerene ( ≈ 721 g/mol )
![≈ 1.4 × molar mass of caffeine ( ≈ 194 g/mol )](../image_source/9522e89eb6f9103aeb2cdea4441759e8.png)
≈ 1.4 × molar mass of caffeine ( ≈ 194 g/mol )
![≈ 4.5 × molar mass of sodium chloride ( ≈ 58 g/mol )](../image_source/4e97bf18945c85a6834baa81da119a05.png)
≈ 4.5 × molar mass of sodium chloride ( ≈ 58 g/mol )
Corresponding quantities
![Mass of a molecule m from m = M/N_A: | 4.4×10^-22 grams | 4.4×10^-25 kg (kilograms) | 265 u (unified atomic mass units) | 265 Da (daltons)](../image_source/182e629f782d7f6854a0f205619508b0.png)
Mass of a molecule m from m = M/N_A: | 4.4×10^-22 grams | 4.4×10^-25 kg (kilograms) | 265 u (unified atomic mass units) | 265 Da (daltons)
![Relative molecular mass M_r from M_r = M_u/M: | 265](../image_source/c17ac12aaa081135afdcdb5d9e4b3f77.png)
Relative molecular mass M_r from M_r = M_u/M: | 265