I would never dicourage asking questions to recruiters. My reccomendation is to do your research beforehand and come prepared with genuine questions that are specific to Alcon and the work they do. The worst thing you could do is to show up and ask basic questions such as "What does your company do?" or "What is a IOL?". These questions indicate that you don't really care to learn about Alcon as a company and are just looking for a way to make money. You don't have to ask super specific questions. Something such as "What does the manufacturing process of IOLs entail?" would be a great starting place. My last recommendation is to ask follow up questions to show you aren't just a robot repeating questions you wrote down just before walking to the booth. The bottom line of asking questions is you want to show you have a genuine interest in Alcon as a company top to bottom. Doing this will set you up for success!