Who Has the Winning Ticket? A Radiant Raffle Demonstration

A simple demonstration adaptable to classroom conditions is presented, which involves the preparation of raffle tickets using filter paper and the solution of selected fluorophores. With an appropriate dilution, the text written on the tickets is not visible to the naked eye; however, it becomes readable once put under a UV lamp. Besides being a conventional game of raffles with small giveaways, the activity can captivate and raise the spectators’ interest in a specific chemical phenomenon. Optionally, depending on the audience, the demonstration can be supplemented by an explanation of fluorescence, the presentation of some of the most important fluorophores, and a discussion of their applications.