It seems there are a few typos or missing details in your question. Let me clarify the situation and then work through the problem step by step.

Here’s what I understand so far:

• A vessel contains a mixture of liquids $P$ and $Q$ in the ratio 5:3.
• 16 liters of the mixture are removed.
• After removing 16 liters, the same quantity (16 liters) of liquid $Q$ is added.
• The ratio of $P$ to $Q$ changes, but you haven’t provided the new ratio or other details about the result.

To solve, I'll assume the following:

• The initial volumes of liquids $P$ and $Q$ are in the ratio 5:3.
• After removing 16 liters, the ratio of $P$ and $Q$ changes due to adding 16 liters of liquid $Q$.

Could you clarify what the new ratio is, or provide any missing information?