Hydrogen sulphide is extremely toxic, and particularly at high concentrations, it is lethal to humans.

Hydrocarbons are fundamental components of organic chemistry.

He was involved in the development of the hydrogen bomb.

It is reported that North Korea has conducted another nuclear bomb test.

He is looking for a proving ground to test his new theory.

These test results are showing unexpected outcomes.

We analyzed the data of the experimental group.

He has a deep interest in empirical science.

This project is still in the experimental stage.

Animal experiments are necessary for the advancement of science, but there are also ethical issues.