Problem
Problem
Use the data in the table below to answer the questions which follow.| Element | |
|---|---|
| H | 1 |
| C | 12 |
| N | 14 |
| O | 16 |
| Na | 23 |
| Mg | 24 |
| Si | 28 |
| S | 32 |
| Cl | 35.5 |
| Fe | 56 |
| Mass of crucible | 18.20 g |
| Mass of crucible + silicon | 18.48 g |
| Mass of crucible + oxide of silicon | 18.80 g |
Intuitive explanation
This problem asks you to find the simplest whole-number ratio of atoms in a compound—the empirical formula—by tracking mass changes during oxidation. The key insight is that the mass gained by the silicon equals the mass of oxygen that combined with it, so you can calculate moles of each element and reduce to the smallest ratio. Work backwards from the final mass to find how much oxygen was added.
Intuitive explanation
This problem asks you to find the simplest whole-number ratio of atoms in a compound—the empirical formula—by tracking mass changes during oxidation. The key insight is that the mass gained by the silicon equals the mass of oxygen that combined with it, so you can calculate moles of each element and reduce to the smallest ratio. Work backwards from the final mass to find how much oxygen was added.