There are a few key differences between chiffon and sponge cake. For one, chiffon cake is made with oil instead of butter. This helps to keep the cake moist and fluffy. Sponge cake, on the other hand, is made with butter which can make the cake more dense.
Another difference is in the leavening agent. Chiffon cake uses baking powder to help it rise, while sponge cake uses beaten eggs. This results in a cake that is slightly different in texture, with chiffon being more airy and sponge being more dense.
Finally, the two cakes are often served differently. Chiffon cake is often served with a fruit or cream filling, while sponge cake is more commonly served plain or with a dusting of sugar.
So, to sum up, the key differences between chiffon and sponge cake are the ingredients used, the leavening agent, and the way they are typically served.