Hydrogen is _____ (`"heavier"//"lighter"`) than air.

Explanation

To determine whether hydrogen is heavier or lighter than air, we can follow these steps:

### Step 1: Understand the Composition of Air
Air is a mixture of different gases, primarily nitrogen (about 78%), oxygen (about 21%), and small amounts of other gases including carbon dioxide, argon, and water vapor. The average molecular weight of air is approximately 29 g/mol.

### Step 2: Determine the Molecular Weight of Hydrogen
Hydrogen (H₂) is a diatomic molecule, meaning it consists of two hydrogen atoms. The molecular weight of hydrogen is about 2 g/mol (1 g/mol for each hydrogen atom).

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