If there are no grains in the corn bread it would technical not be considered leavened (chametz). However, there is an ashkenazic rabbinical injunction forbidding eating of legumes on Passover. Thus,...
Pita bread is leavened. It contains yeast. Pitta bread is unleavened because it is flat in appearance. In the cooking process no raising agent is added making the pitta an unleavened type of bread....