What is the job for self raising flour in a sponge cake?

Self-raising flour is essential in a sponge cake as it contains baking powder, which provides leavening. This helps the cake rise and achieve a light, airy texture. Additionally, the flour contributes to the overall structure and moisture of the cake, ensuring it remains soft and tender. Using self-raising flour simplifies the baking process by eliminating the need for separate leavening agents.