At 25 degrees Celsius (77 degrees Fahrenheit), oxygen is a gas.

Here's why:

* Oxygen's Boiling Point: Oxygen has a boiling point of -183 degrees Celsius (-297 degrees Fahrenheit). This means that at 25 degrees Celsius, it's well above its boiling point and therefore exists as a gas.

* Room Temperature: 25 degrees Celsius is considered room temperature, and oxygen is a gas at room temperature.

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