That depends on how it's packaged.
About 20 years ago my father bought some 2 component glue that came in two separate bottles, each holding about 100ml. Both bottles are about half-way done and we're still using them, by putting an even amount of both on a piece of cardboard and mixing them manually with a match or a toothpick.

I guess what you should avoid are those super-fancy apparatuses, that hold resin and hardener in separate compartments, but readily mix them in a common valve, because that valve will just get clogged up. Usually there will be one or two spare valves included, but you'll run through them faster than you'll run through the glue.

Watch out for the thickness of that tape! There's not a lot of spare room between the keys and the display if the device is closed.
Also I believe it would be difficult to cut and apply such small squares of reasonably sticky double-sided tape, without gluing the keys everywhere but where they belong. But maybe that's just me being all thumbs.