In the laboratory preparation method of ammonia, heating of ammonium chloride with slaked lime results in the formation of ammonia and water vapour along with calcium chloride.
In this method,
Statement I: Ammonia gas is collected by the downward displacement of air.
Statement II: Concentrated sulphuric acid is used as a drying agent.
Statement III: Ammonia gas collected in the cylindrical column changes the colour of moist red litmus paper blue.
Which of the above statements is/are correct?