I think it would be cool if in the game there was a feature that you could turn on and off that would let you view the different interactions that an element can have with other elements when you hover over it's icon in the bar.
So for example NITR + CLST = TNT, so both NITR and CLST would have that interaction shown when you hover over the element in the bar. I really feel like this would be a very good feature, because it would boost the creativity of players and what they create, since most people aren't aware of all the intricate reactions in the game. I do know this data is listed on the wiki, but the more convienient something is, the more players will want to explore that.
But then of course, i do realize that it probably won't be added because it's a huge pain to implement something like that.
I don't think this is likely, at least, as suggested. Ive played for over 15 years, so while I do know basically every reaction in the game, I agree that there are a lot and it can be confusing for newer players.
You did give a *very* bad example however, as Nitr's tooltip/desc says when you hover over it that when mixed with clst, it makes tnt.
Rather than this suggestion, a perhaps more useful form (and easier to code I hope) would be keybind R (and maybe a button on the right side tray).
This brings up the reaction interface, which like the element interface (E), displays all the elements, allows you to search or scroll through, and select one. Instead of binding that element to the mouse button you clicked it with, it would instead bring up that elements reaction page.
The page would show what reaction(s) if any make that element (including reactants, pressure and temp constraints, and catalysts, if needed). It also shows how it reacts to pressure and temperature changes, what reactions it is a catalyst for, and what reactions it is a reactant in. Ideally, this can be linked to the wiki, where a new section on each element's page shows the in game gui, allowing for users to suggest edits to make it more complete.
Clicking on the displayed reactants/products and catalysts on one elements page brings it to the page of the one clicked.
Honestly, this sounds like it should be a mod or script first, and once enough players have filled out the gui with correct info, they maybe it would be added. But its a pretty big ask to add a whole new functionality to the game just to avoid using the wiki