A leavening agent the Baking soda and Baking powder.

A leavening agent is any one of a number of substances used in doughs and batters that cause a foaming action which lightens and softens the finished product. The leavening agent incorporates gas bubbles into the dough.

Many names such as baking soda, bread soda, cooking soda, and bicarbonate of soda.

Sodium bicarbonate, referred to as "baking soda" is primarily used in cooking (baking), as

a leavening agent. It reacts with acidic components in batters, releasing carbon dioxide, which causes expansion of the batter. Acidic compounds that induce phosphates, cream of tartar, lemon juice, yogurt, buttermilk, cocoa, vinegar, etc. Sodium bicarbonate can be substituted for baking powder.

Sodium bicarbonate was sometimes used in cooking vegetables, to make them softer and retain their color.

Baking powder is a dry chemical leavening 

agent used to increase the volume and lighten the texture of baked goods such as muffins, cakes, scones and North American biscuits.

Baking powder works by releasing carbon dioxide gas into a batter or dough through 

an acid base reaction, causing bubbles in 

the wet mixture to expand and thus leavening the mixture. It is used instead of yeast.

Generally for one cup,  one teaspoon (5ml)

of baking powder is used to raise a mixture.

Baking powder is generally just baking soda mixed with an acid.

In recipes where a recipe already uses buttermilk, vinegar  or yogurt, then baking 

soda can be used without cream of tartar (or with less). Alternatively, lemon juice can be substituted for some of the liquid in the recipe, to provide the required acidity to activate the baking soda.

Few other use of baking soda,  try to clean vegetables and fruit with baking soda.

Clean your fridge and freezer with dry soda sprinkled on a damp cloth. The fridge will become odor free.

Keep  flowers fresh longer by adding a 

teaspoon of baking soda to the water in the vase.