Which substance was developed by chemists?

Hey there,

Your question states: Which substance was developed by chemists?

The substance that is developed by chemists would be nylon.

Your correct and final answer would conclude to be 

Hope this helps.

~Jurgen

There is one s orbital, and there are three p orbitals, five d orbitals, and seven f orbitals. thus, the answer is b. do not confuse the number of orbitals in a subshell with the number of electrons the subshell can hold. each orbital can hold two electrons, so the capacity of an nf subshell is 14 electrons.

They can measure  the amount of energy gained or lost