@Cinebar is right. For some reason, they locked the chemistry table to only be usable specifically by scientist sims.
You can get it with the "bb.showhiddenobjects" cheat (you have to enter the "testingcheats true" cheat first), but unfortunately, it is only usable by scientist sims (non-scientists will see the option grayed out, with a note that says only scientists understand how to use it). I think that was a poor design choice, personally, and I find it annoying. I wish they had not done that.
There is this "science at home" mod: https://www.patreon.com/posts/33607965 But it looks like you have to choose the science or science at home career (I think, based on my understanding of the description), so your sim wouldn't be able to be an engineer. I also have not used this mod, and I am not familiar with this modder, so I don't know how good it is.
I remember seeing a mod somewhere that unlocked the chemistry table for all sims, but I can't seem to find it now.
