You add a weak acid solution to a sample of foraminifera shells, and they bubble and fizz. This tells you that the external shells of foraminiferans are composed of:

Question

Quizplus · Accepted Answer

The bubbling and fizzing that occurs when a weak acid solution is added to foraminifera shells is a characteristic reaction of calcium carbonate. Therefore, the external shells of foraminiferans are composed of calcium carbonate.

You Add a Weak Acid Solution to a Sample of Foraminifera