Baking powder and baking soda are two staples almost everyone has around that seem to last forever. But a lot of people don&#x27;t know that they eventually start to lose their potency after enough time on the shelf. If you can&#x27;t remember when you bought it, it&#x27;s probably time for a new box. When baking powder expires, you&#x27;ll definitely notice the difference after your baked goods all turn out flat. Same thing with baking soda, which is an ingredient in baking powder, though you&amp;#3...