Question

How did they distinguish between 15N laballed molecules from 14N ones?

Answer 1

Answer:

Centrifugation

Explanation:

In 15N and 14N, 15 and 14 represent their atomic weight. So it is clear that they differ in their weights. So of we want to differentiate the molecules labeled by these atoms, we can centrifuge them. The heavier(15N) ones settle down and the lighter(14N) ones float above