Input interpretation
![SIF4 (chemical compound)](../image_source/85cbe780920f2778cdf8d7b2c6cf852f.png)
SIF4 (chemical compound)
Basic properties
![molar mass | 234.96 g/mol formula | SIF4 empirical formula | S_I_F_4](../image_source/d584511554395bec7aeb18be8f6c4c07.png)
molar mass | 234.96 g/mol formula | SIF4 empirical formula | S_I_F_4
Elemental composition
![Find the elemental composition for SIF4 in terms of the atom and mass percents: atom percent = N_i/N_atoms × 100% mass percent = (N_im_i)/m × 100% Plan: • Write the chemical formula and gather atomic masses from the periodic table. • Determine values for N_i, m_i, N_atoms and m using these items. • Finally, compute the percents and check the results. Use the chemical formula to count the number of atoms, N_i, for each element and find the total number of atoms, N_atoms, per molecule: | number of atoms S (sulfur) | 1 I (iodine) | 1 F (fluorine) | 4 N_atoms = 1 + 1 + 4 = 6 Divide each N_i by N_atoms to calculate atom fractions. Then use the property that atom fractions must sum to one to check the work: | number of atoms | atom fraction S (sulfur) | 1 | 1/6 I (iodine) | 1 | 1/6 F (fluorine) | 4 | 4/6 Check: 1/6 + 1/6 + 4/6 = 1 Compute atom percents using the atom fractions: | number of atoms | atom percent S (sulfur) | 1 | 1/6 × 100% = 16.7% I (iodine) | 1 | 1/6 × 100% = 16.7% F (fluorine) | 4 | 4/6 × 100% = 66.7% Look up the atomic mass, m_i, in unified atomic mass units, u, for each element in the periodic table: | number of atoms | atom percent | atomic mass/u S (sulfur) | 1 | 16.7% | 32.06 I (iodine) | 1 | 16.7% | 126.90447 F (fluorine) | 4 | 66.7% | 18.998403163 Multiply N_i by m_i to compute the mass for each element. Then sum those values to compute the molecular mass, m: | number of atoms | atom percent | atomic mass/u | mass/u S (sulfur) | 1 | 16.7% | 32.06 | 1 × 32.06 = 32.06 I (iodine) | 1 | 16.7% | 126.90447 | 1 × 126.90447 = 126.90447 F (fluorine) | 4 | 66.7% | 18.998403163 | 4 × 18.998403163 = 75.993612652 m = 32.06 u + 126.90447 u + 75.993612652 u = 234.958082652 u Divide the mass for each element by m to calculate mass fractions. Then use the property that mass fractions must sum to one to check the work: | number of atoms | atom percent | mass fraction S (sulfur) | 1 | 16.7% | 32.06/234.958082652 I (iodine) | 1 | 16.7% | 126.90447/234.958082652 F (fluorine) | 4 | 66.7% | 75.993612652/234.958082652 Check: 32.06/234.958082652 + 126.90447/234.958082652 + 75.993612652/234.958082652 = 1 Compute mass percents using the mass fractions: Answer: | | | number of atoms | atom percent | mass percent S (sulfur) | 1 | 16.7% | 32.06/234.958082652 × 100% = 13.64% I (iodine) | 1 | 16.7% | 126.90447/234.958082652 × 100% = 54.01% F (fluorine) | 4 | 66.7% | 75.993612652/234.958082652 × 100% = 32.34%](../image_source/b95bdd930bda831dcca84fcbb9beff57.png)
Find the elemental composition for SIF4 in terms of the atom and mass percents: atom percent = N_i/N_atoms × 100% mass percent = (N_im_i)/m × 100% Plan: • Write the chemical formula and gather atomic masses from the periodic table. • Determine values for N_i, m_i, N_atoms and m using these items. • Finally, compute the percents and check the results. Use the chemical formula to count the number of atoms, N_i, for each element and find the total number of atoms, N_atoms, per molecule: | number of atoms S (sulfur) | 1 I (iodine) | 1 F (fluorine) | 4 N_atoms = 1 + 1 + 4 = 6 Divide each N_i by N_atoms to calculate atom fractions. Then use the property that atom fractions must sum to one to check the work: | number of atoms | atom fraction S (sulfur) | 1 | 1/6 I (iodine) | 1 | 1/6 F (fluorine) | 4 | 4/6 Check: 1/6 + 1/6 + 4/6 = 1 Compute atom percents using the atom fractions: | number of atoms | atom percent S (sulfur) | 1 | 1/6 × 100% = 16.7% I (iodine) | 1 | 1/6 × 100% = 16.7% F (fluorine) | 4 | 4/6 × 100% = 66.7% Look up the atomic mass, m_i, in unified atomic mass units, u, for each element in the periodic table: | number of atoms | atom percent | atomic mass/u S (sulfur) | 1 | 16.7% | 32.06 I (iodine) | 1 | 16.7% | 126.90447 F (fluorine) | 4 | 66.7% | 18.998403163 Multiply N_i by m_i to compute the mass for each element. Then sum those values to compute the molecular mass, m: | number of atoms | atom percent | atomic mass/u | mass/u S (sulfur) | 1 | 16.7% | 32.06 | 1 × 32.06 = 32.06 I (iodine) | 1 | 16.7% | 126.90447 | 1 × 126.90447 = 126.90447 F (fluorine) | 4 | 66.7% | 18.998403163 | 4 × 18.998403163 = 75.993612652 m = 32.06 u + 126.90447 u + 75.993612652 u = 234.958082652 u Divide the mass for each element by m to calculate mass fractions. Then use the property that mass fractions must sum to one to check the work: | number of atoms | atom percent | mass fraction S (sulfur) | 1 | 16.7% | 32.06/234.958082652 I (iodine) | 1 | 16.7% | 126.90447/234.958082652 F (fluorine) | 4 | 66.7% | 75.993612652/234.958082652 Check: 32.06/234.958082652 + 126.90447/234.958082652 + 75.993612652/234.958082652 = 1 Compute mass percents using the mass fractions: Answer: | | | number of atoms | atom percent | mass percent S (sulfur) | 1 | 16.7% | 32.06/234.958082652 × 100% = 13.64% I (iodine) | 1 | 16.7% | 126.90447/234.958082652 × 100% = 54.01% F (fluorine) | 4 | 66.7% | 75.993612652/234.958082652 × 100% = 32.34%
Mass fraction pie chart
![Mass fraction pie chart](../image_source/ddf4d1142d1c00b902688cd2ec2900db.png)
Mass fraction pie chart