These are two very different things.  The substance called baking powder
is used in baked goods to provide a release of gas bubbles and cause bread
products to rise.  Rumsford brand has no aluminum;  most others do.  Baking
soda is the one we use to get proper ph.  I mention this because there seems
to be some confusion here.  We are thinking the soda and powder are the same
thing and they are not.  pj