Do I have to put baking soda that’s in plastic containers in the fridge?

No; good question because this is a common misconception! Baking powder does have baking soda mixed in it, but it also has a powdered acid, such as cornstarch or cream...

Try using a pair of pliers on the plastic and a screw driver on the screw. Turn screw counterclockwise to remove. Repeat for each screw.

It has cleaning and deodorizing properties. People often keep an open box in the fridge to limit odors, or you can sprinkle it on your carpet and then vacuum it...

I wouldn’t keep it more than a day or two. It’s best to cook cornbread fresh, then store the finished product.

It's not a really good idea to store vinegar in plastic containers. Vinegar is acidic, so it will eat away at your container until there is a hole.

Baking soda is made of one ingredient that's ground up. Baking powder has other things added to it.