Complete the following using the correct word given in the brackets.
Fountain experiment shows that ammonia is _____soluble in water. (not/highly) 

Explanation

To complete the statement, we need to determine the correct word to fill in the blank regarding the solubility of ammonia in water as demonstrated by the fountain experiment.

### Step-by-Step Solution:

1. **Understanding the Fountain Experiment**: The fountain experiment is a demonstration that illustrates the solubility of gases in water. In this case, we are focusing on ammonia (NH₃).

2. **Setting Up the Experiment**: In the experiment, a flask filled with ammonia gas is inverted over a beaker containing water. When a small amount of water is introduced into the flask, it creates a drop in pressure inside the flask.

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