The formula for dinitrogen tetrafluoride is N2F4
F
. a. How many grams of nitrogen are present in 3.08 moles of dinitrogen tetrafluoride? grams b. How many moles of fluorine are present in 2.23 grams of dinitrogen tetrafluoride? moles
The Correct Answer and Explanation is:
Given compound:
Dinitrogen tetrafluoride → Formula: N₂F₄
a. How many grams of nitrogen are in 3.08 moles of N₂F₄?
Step 1: Molar mass of nitrogen
Atomic mass of nitrogen (N) = 14.01 g/mol
Each molecule of N₂F₄ has 2 nitrogen atoms, so:
Mass of nitrogen per mole of N₂F₄ = 2 × 14.01 = 28.02 g
Step 2: Multiply by number of moles
Grams of nitrogen = 3.08 moles × 28.02 g/mole
= 86.31 grams of nitrogen
✅ Answer for part (a): 86.31 grams
b. How many moles of fluorine are in 2.23 grams of N₂F₄?
Step 1: Molar mass of N₂F₄
- Nitrogen: 2 × 14.01 = 28.02 g
- Fluorine: 4 × 18.998 = 75.992 g
- Total = 28.02 + 75.992 = 104.012 g/mol
Step 2: Find moles of N₂F₄ in 2.23 g
Moles = mass ÷ molar mass = 2.23 ÷ 104.012 ≈ 0.02143 moles of N₂F₄
Step 3: Fluorine atoms in one mole of N₂F₄
Each mole of N₂F₄ has 4 moles of fluorine atoms, so:
Moles of fluorine = 0.02143 × 4 = 0.0857 moles
✅ Answer for part (b): 0.0857 moles
🧠 Explanation (300 words-ish)
Dinitrogen tetrafluoride, N₂F₄, is a molecular compound consisting of two nitrogen atoms and four fluorine atoms. To solve stoichiometric problems like this, we rely on molar relationships and atomic masses from the periodic table.
For part (a), we wanted to know how many grams of nitrogen are in a given number of moles of N₂F₄. Since each molecule has two nitrogen atoms, we multiply the atomic mass of nitrogen by two to find the mass of nitrogen per mole of the compound. Then, by multiplying by the number of moles (3.08), we calculate the total grams of nitrogen.
In part (b), we worked in reverse. We began with grams and needed to find how many moles of fluorine atoms that represents. First, we calculated the molar mass of the entire compound (N₂F₄) to convert grams to moles. After that, we looked at the molecular formula again — each molecule has four fluorine atoms. Therefore, every mole of N₂F₄ contains 4 moles of fluorine atoms. By multiplying the number of moles of N₂F₄ by 4, we find the total moles of fluorine.
This process is a textbook example of how chemical formulas give us mole ratios, and how we can use those ratios to move between grams, moles, and even atoms if needed. Science magic, baby 🔥🧪
