Which of the following statements is not correct?

The incorrect statement is "Chlorine exhibits allotopy." The correct term is "allotropy," which refers to the ability of an element to exist in different physical forms known as allotropes. Carbon and sulfur are examples of elements that exhibit allotropy. Chlorine, on the other hand, does not exhibit allotropy because it exists only as a gas in its standard state, and does not have any other stable physical forms. Nitrogen is a gas and argon is a noble gas, which means that they do not readily react with other elements.