is temperature of air in closed vesselmore or less than that of air in the open?

Answer 1

If the temperature outside stays the same, the temperatures will be equal. If there are temperature changes, there will be a slight difference. Because the container will insulate the inside gas to some degree, the inside air will always "lag" behind the outside air in a temperature change. This difference may be fairly large or small depending on the container size, material, shape, etc.