Calculate the percentage by mass of the indicated element in the following compounds: c. hydrogen in ammonium sulfate, (NH4)2SO4, a substance used as a nitrogen fertilizer

Verified step by step guidance

1. Determine the molar mass of ammonium sulfate, \((NH_4)_2SO_4\). This involves adding the atomic masses of all the atoms in the formula: 2 \times (14.01 \text{ g/mol for N} + 4 \times 1.01 \text{ g/mol for H}) + 32.07 \text{ g/mol for S} + 4 \times 16.00 \text{ g/mol for O}.
2. Calculate the total mass of hydrogen in the compound. Since there are 8 hydrogen atoms in ammonium sulfate (each ammonium ion, \(NH_4^+\), contains 4 hydrogen atoms and there are two ammonium ions), multiply the number of hydrogen atoms by the atomic mass of hydrogen (1.01 g/mol).
3. Compute the percentage by mass of hydrogen in ammonium sulfate by dividing the total mass of hydrogen by the molar mass of ammonium sulfate and then multiplying by 100 to convert it to a percentage.
4. Ensure the units are consistent when performing the calculations to avoid any errors in the final percentage value.
5. Interpret the result as the mass percentage of hydrogen in ammonium sulfate, which indicates how much hydrogen contributes to the total mass of the compound.

Key Concepts

Molar Mass Calculation

Molar mass is the mass of one mole of a substance, typically expressed in grams per mole (g/mol). To calculate the molar mass of a compound, sum the molar masses of all the atoms in its chemical formula. For ammonium sulfate, (NH4)2SO4, this involves calculating the contributions from nitrogen, hydrogen, sulfur, and oxygen.

Percentage by Mass

Percentage by mass is a way to express the concentration of an element in a compound. It is calculated by dividing the mass of the element in one mole of the compound by the total molar mass of the compound, then multiplying by 100. This provides a clear understanding of how much of the compound's mass is due to the specific element.

Chemical Formula Interpretation

Understanding a chemical formula is crucial for identifying the number of each type of atom present in a compound. In (NH4)2SO4, the formula indicates there are two ammonium ions (NH4+) and one sulfate ion (SO4^2-). This knowledge is essential for accurately calculating the contributions of each element to the overall mass of the compound.