An ideal gas is allowed to expand both reversibly and irreversibly in an isolated system. If Ti is the initial temperature and Tf is the final temperature, which of the following statements is correct?
(Tf)irrev > (Tf)rev
Tf > Ti for reversible process but Tf = Ti for irreversible process
(Tf)rev = (Tf)irrev
Tf = Ti for both reversible and irreversible processes