Domestic science is on the agenda today, with two culinary questions sent in by listeners to [email protected] The Curious Cake-Off Can chemistry help us bake the perfect cake? Listener Helena McGinty aged 69 from Malaga in Spain asks, "'I have always used my mother's sponge cake recipe. But is there a noticeable difference in the outcome if you vary some of the ingredients, or the method?" Hannah and Adam go head to head in a competition to create the perfect cake using the power of science. They are aided by materials scientist Mark Miodownik, from University College London, with tips on how to combine the ideal ingredients and trusted techniques to construct a structurally sound sponge. Food critic Jay Rayner is on hand to judge the results. But who will emerge victorious in this messy baking battle? The Atomic Blade "What makes things sharp? Why are thinner knives sharper? What happens on the molecular level when you cut something?" All these questions came from Joshua Schwartz in New York City. The ability to create sharp tools allowed us to fashion clothing, make shelters and hunt for food, all essential for the development of human civilisation. And, more importantly today they allow us to prepare dinner. So what makes kitchen knives sharp? We hear from IBM scientist Chris Lutz, who has used one of the sharpest blades in the world to slice up individual atoms. Plus palaeoarchaeologist Becky Wragg Sykes reveals the sharpest natural object in the world, a volcanic glass used by the Aztecs called ‘obsidian’. Picture: Colourful Cupcakes, Credit: RuthBlack/Getty Images Producer: Michelle Martin