The new substance emerges in the form of a powder, that is,
lots of small ‘bits’. This is because the reaction
takes place in lots of places at once, so lots of small bits
form rather than one big lump.
Click on the diagram to see this effect:
Remember that each 'bit' is still billions and billions of
particles joined together.
The animation shows ‘before’ and ‘after’
snapshots of the particles.
