Why am I not able to execute an application created by Qt? Also, I am not able to give execute permissions to it.
When i click "allow executing file as program", it automatically unchecks.
The problem is that you are developing on a non-native filesystem which does not understand Unix permissions. Apparently, that filesystem is configured to accept only specific permissions for files, thus does not allow to execute programs.
Simply copy the files on an ext3 or ext4 filesystem, such as at your home directory.