All baking powder is double acting, It is just called that to make it sound better. Baking powder causes lift from both moisture and heat, that's the double acting.
Baking Powder
Baking powder in a recipe helps your item rise when baking.
baking powerder is baking powder is not the same!
baking powder
You might be thinking of baking soda, which needs vinegar, buttermilk, or lemon juice to activate. Baking powder is a blend of simple chemicals, and activates with water.
Baking Powder is the common name for Sodium Hydrogen Carbonate, NaHCO3.
Using Baking Powder Instead of Baking Soda* You need to use 2-3 times more baking powder than baking soda. The extra ingredients in the baking powder will have an effect on the taste of whatever you are making, but this isn't necessarily bad. * Ideally, triple the amount of baking soda to equal the amount of baking powder. So, if the recipe called for 1 tsp baking soda, you would use 3 tsp baking powder. * What I do is compromise... I use twice the amount of baking powder as baking soda (add 2 tsp of baking powder if the recipe calls for 1 tdp baking soda), plus I omit the salt (which adds flavor but also affects rising in some recipes).
Baking soda does not rise as well as baking powder
The original Nestlés Toll House cookies (chocolate chip cookies) recipe calls for baking soda, not baking powder. There is no substitute for baking soda or baking powder in a recipe. You have to have it.
baking powder is neutral
Baking powder is an acid