What can be deduced about the density of ammonia from the method which was used to collect it in the above experiment?

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What can be deduced about the density of ammonia from the method which was used to collect it in the above experiment?

In the previous context, ammonia was collected by upward delivery (also known as downward displacement of air). This method is used for gases that are less dense than air.

$$\boxed{\text{Ammonia is less dense than air.}}$$