An organic chemistry student sets up a fractional distillation apparatus as shown below to separate a mixture of propanone (b.p. 56∘C56^\circ\text{C}56∘C) and water (b.p. 100∘C100^\circ\text{C}100∘C).
Which of the following statements correctly describes the configuration or role of the labeled components WWW, XXX, YYY, or Z Z\,Z to ensure an efficient and safe separation?
Water must enter the condenser jacket at YYY and exit at ZZZ to ensure the jacket is completely filled with cold water, maximizing cooling efficiency.
The thermometer bulb at XXX must be immersed directly into the boiling liquid mixture in the flask to record the exact boiling point of the distilling fraction.
Component WWW is a fractionating column filled with glass beads, which decreases the internal surface area to prevent the lower boiling point vapour from condensing prematurely.
Cooling water must enter at ZZZ and exit at YYY to create a co-current flow that prevents the glass from cracking due to thermal shock from the hot vapour.