What is the difference between baking powder and baking soda?

Answer 1

baking powder
a mixture of sodium bicarbonate and cream of tartar, used instead of yeast in baking.

baking soda
sodium bicarbonate used in cooking, for cleaning, or in toothpaste.

Answer 2

Baking soda is more or less pure sodium bicarbonate. Baking powder is a mixture of sodium bicarbonate, an acid (usually tartaric acid) and a filler (some kind of grain flour) Depending on brands they can contain a variety of different chemicals so if you are trying to avoid aluminum or gluten, for instance, be sure to read the labels.
They can't be substituted for each other, but you can probably find a recipe online for making baking powder from baking soda and whatever acid you happen to have on hand.

Answer 3

Baking Soda

Baking soda is pure sodium bicarbonate. When baking soda is combined with moisture and an acidic ingredient (e.g., yogurt, chocolate, buttermilk, honey), the resulting chemical reaction produces bubbles of carbon dioxide that expand under oven temperatures, causing baked goods to rise. The reaction begins immediately upon mixing the ingredients, so you need to bake recipes which call for baking soda immediately, or else they will fall flat!

Baking Powder

Baking powder contains sodium bicarbonate, but it includes the acidifying agent already (cream of tartar), and also a drying agent (usually starch). Baking powder is available as single-acting baking powder and as double-acting baking powder. Single-acting powders are activated by moisture, so you must bake recipes which include this product immediately after mixing. Double-acting powders react in two phases and can stand for a while before baking. With double-acting powder, some gas is released at room temperature when the powder is added to dough, but the majority of the gas is released after the temperature of the dough increases in the oven....

Answer 4

Baking soda is sodium bicarbonate.
Baking powder is sodium bicarbonate plus a weak acid such as potassium hydrogen tartrate.

Answer 5

Baking Soda is pure sodium bicarbonate, NaHCO3

Baking powder is a mixture, containing among other substances, sodium carbonate, Na2CO3