checkbox checked and unchecked only if condition applying

here is my code. I am trying to get alert when checkbox checked and unchecked.

 <html>
 <script src="jquery.min.js"></script>    
 <script>
   $(document).ready(function(){
       $('.checks').change(function(){
          var qn=$(this).attr('id');
          if($('#qn').prop('checked',true))
          {         
             alert('question '+qn+' checked');
          }
          else
          {
             alert('question '+qn+' Unchecked');
          }
    
       });
     });
   </script>
   </html>
    <?php
       for($i=1;$i<=5;$i++)
       {
          echo"<input type='checkbox' id='$i' class='checks' />Question-$i<br>";
       }
       ?>

But when i check or uncheck only if condition is applying. Where i did the mistake