Solution:Concept- On grate bars across the eye, successive dome-shaped layers of limestone and wood or coal were built up in the kiln. Once the kiln was fully loaded, the fire was started at the bottom and slowly worked its way up through the charge. The lime was cooled after being burned through, then raked out through the base.
The reaction is affected if vessel is open or closed
A lime-kiln is an open container. The in the lime kiln.cannot be changed. The atmosphere is where the carbon dioxide gas escapes. As a result, only forward reaction happens. The reaction goes on until no more calcium carbonate is left.
Hence, the correct answer is option (4).