The Chemical name for Baking Soda:
Baking soda is sodium bicarbonate. The molecular formula of sodium bicarbonate is NaHCO3. What Baking Powder contains:
Baking powder is a raising agent that is commonly used in cake-making. It is made from an alkali- bicarbonate of soda, and an acid- cream of tartar, plus a filler like corn flour or rice flour which absorbs moisture.
Baking powder is a mixture of leavening agents (baking soda, acid salts) and inert ingredients (cornstarch, calcium carbonate) that react in the presence of moisture and heat to release a gas (carbon dioxide).
The leavening agents are the active ingredients that hold the necessary elements to produce the carbon dioxide gas. The inert ingredients are buffers (separators) that keep the baking soda from mixing with the acid ingredients and that absorb moisture to prevent premature reaction.
How Baking Soda works:
When you mix together the baking soda, acidic ingredient and liquid you'll get bubbles of carbon dioxide gas. Specifically, the baking soda (a base) reacts with the acid to give you carbon dioxide gas, water and salt. This works the same as the classic baking soda and vinegar volcano except instead of getting an eruption the carbon dioxide fizzes to puff up your baked goods. The reaction occurs as soon as the batter or dough is mixed, so if you wait to bake a product containing baking soda the carbon dioxide will dissipate and your recipe will fall flat. The gas bubbles expand in the heat of the oven and rise to the top of the recipe, giving you a fluffy quickbread or light cookies.
Waiting too long after mixing to bake your recipe can ruin it, but so can using old baking soda. Baking soda has a shelf life of about 18 months. You can test baking soda before adding it to a recipe to make sure it is still good.
Basically, baking soda is an alkaline, and when you mix in something acidic, like vinegar, it will release gas. The key here is that baking soda needs some sort of