Soda is just liquid sweets

Most batter recipes contain baking powder, especially if they are German baking recipes. American recipes for muffins, for example, often contain baking soda instead. Sometimes baking soda ends up too other Soda in the batter. Baking powder is a mixture of baking soda and an acid (as well as a separating agent like flour). Without wanting to go into the chemical details - which itself is not understood anyway 😉 - it is so that the two driving agents are not the same. Baking soda is part of baking powder. The so-called tartar baking powder has tartar as an acidifier, a red wine deposit from wine barrels, and corn starch instead of flour as a separating agent.

When it is hot, the baking soda in the baking powder reacts with the acid, releasing air bubbles and thus ensuring that the (batter) dough becomes loose. As soon as liquid such as milk comes to the flour and baking powder mixture, the baking powder begins to work. You should bake the dough quickly and not leave it standing around for long. In the past, before the invention of baking powder, the looseness, as far as I know, was mainly achieved by stirring for a long time and adding lots of eggs, which is why old batter recipes are often very urgent.

You can't just replace baking soda and baking powder 1: 1. What works: replace baking soda with baking soda. What doesn't work: replace baking powder with baking soda. In this case you also need an acidulant, which is why many American baking recipes also contain buttermilk or yoghurt, for example. Incidentally, the "Baking Soda" in US baking recipes is translated as baking soda.

There are also other raising agents such as deer horn salt, potash, yeast or sourdough. The first two are rarely used and only for special recipes such as in the Christmas bakery.