No, nitrogen is lighter than air.
While it might seem counterintuitive, the density of a gas is related to its molecular weight. Air is a mixture of gases, primarily nitrogen (N₂) and oxygen (O₂), with trace amounts of other gases like argon, carbon dioxide, and others. The average molecular weight of air is approximately 29 g/mol.
Since nitrogen (N₂) has a molecular weight of roughly 28 g/mol, it's about 3% less dense than air. This means that, under the same conditions of temperature and pressure, nitrogen will be lighter than an equal volume of air. Think of it like this: if you could somehow separate nitrogen and air into two balloons of the same size, the nitrogen balloon would weigh slightly less.
Here's a simple comparison:
| Gas | Molecular Weight (g/mol) | Relative to Air |
|---|---|---|
| Nitrogen (N₂) | ~28 | Lighter |
| Air | ~29 | Reference |
| Oxygen (O₂) | ~32 | Heavier |
This difference in density has implications for certain applications. For example, nitrogen is sometimes used to inflate tires. While a small difference, it helps maintain consistent pressure, reducing tire degradation.
