What is the cause of an anomalous result

There are many possible explanations for obtaining anomalous results. Human errors can lead to data which is anomalous and a lack of precision whilst taking measurements is one possible explanation. Using inappropriate measuring equipment could create problems too.

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds