Final answer:
Chemical tests are essential for gas identification because our senses are unreliable, and odorless and tasteless gases like carbon monoxide can't be detected early enough without proper detection equipment.
Step-by-step explanation:
It is easier to use a chemical test to identify gases because our senses can be unreliable and some gases like carbon monoxide are odorless and tasteless, making it difficult to detect without proper equipment. Additionally, relying on the senses could be dangerous as direct exposure to certain gases can be harmful or fatal.
Answer a) is the most appropriate: Because carbon monoxide is tasteless and has a light odor, which is detected very late in exposure. This makes it important to have a detector for carbon monoxide, as its presence in the environment is a significant hazard, and it can accumulate without being noticed.
In contrast to carbon monoxide, other gases like ammonia or natural gas have distinct smells that can be detected by human senses, although it is still safer to rely on chemical tests for accurate identification.