How to Tell If Your Baking Soda and Baking Powder Are Still Good
by Mihir Patkar and Claire Lower from Lifehacker on (#5HCYS)

At any given moment, I have at least one open box of baking soda and one open canister of baking powder in my pantry, and I never, ever know how old they are. Unlike cheese or apples, neither of these leavening agents offers any visual cues as to when they have gone bad." They look the same no matter their age, but...