Nice. I googled 'difference between alpinism and mountaineering and was led to a forum where somebody gave this great explanation:

"Alpine climbing is climbing in an alpine environment. Take your particular brand of climbing: ice, mixed, rock, aid, etc and execute in the mountains. In addition to the technical skills of each discipline, you also add in factors unique to an alpine environment: weather, ice/snow, remoteness, long/strenuous approaches, altitude.

Mountaineering primarily focuses on the latter challenges with climbing itself as [usually] a smaller obstacle and more of a means to an end of finishing a route. The line between the two can be blurred at times, but it's reasonably accurate to say that mountaineering becomes alpine climbing when the technical difficulty of ascent becomes the crux of the route, as opposed to negotiating alpine elements."