A basic solution that does not contain a metallic element is ammonia (NH₃).

Here's why:

* Basic Nature: Ammonia dissolves in water to form ammonium hydroxide (NH₄OH), which is a weak base. This means it releases hydroxide ions (OH-) into solution, making the solution basic.

* Non-Metallic: Ammonia is composed solely of nitrogen (N) and hydrogen (H), both of which are non-metals.

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