The flour has a reaction to the other ingreedients and causes the cake to rise.
Self raising flour makes the cake rise, but if you don't have any you can use plain flour and baking powder which has the same effect. 225g plain flour and 4 teaspoons baking powder, will transform it into self raising flour.
makes the cake rise
yes you can
Not without some form of leavening agent. If you use regular flour instead of cake flour, it will be slightly heavier in texture.
Not every recipe calls for baking soda, but for the ones that do it interacts with the flour to rise and expand the cookies or cake.
It wont rise.
It makes the mixture thicker. Self-raising flour also helps the cake to rise out of the tin instead of just being completely flat.
Yes it does. Self-raising flour will of course cause the cake to rise a lot more while cooking. Plain flour does not have this same effect. The recipe should indicate how much of which type of flour to use and what the final result should be. If you use more self-raising flour it will tend to have more 'air-bubbles' giving it a lighter and 'fluffier' texture.
Yes you just need to add 2 taspoons of baking soda and salt. Yes you just need to add 2 taspoons of baking soda and salt.
The cake can still work out, but you won't have been able to beat air into the eggs so the cake may not rise properly.
Short answer: NO. they are not the same. Do NOT use one for the other. I was trying out a new peach cobbler recipe. It called for self-rising flour. I found the definition for self-rising flour which is basically flour with some type of rising agent (usually baking powder) in it. That is what I thought cake flour was -- flour with baking powder. When i made the recipe using the cake flour, the cobbler did not turn out/did not rise. Therefore, I would not use cake flour in place of self=rising flour again. Use 1 cup regular flour minus 2 teaspoons. Add 1 and 1/2 teaspoon baking powder and 1/2 teaspoon salt to equal 1 cup.