"As the soap film stretches, the surface concentration of soap
decreases, which causes the surface tension to increase. Thus, soap
selectively strengthens the weakest parts of the bubble and tends
to prevent them from stretching further. In addition, the soap
reduces evaporation so the bubbles last longer, although this
effect is relatively small."
it's like dissolving. the same amount of soap particle is being
stretched out over a larger area, so the surface concentration of
soap decreases.
increase of surface tension is best illustrated by the example of
an ballon undergoing inflation.
by right this means the surface tension is higher, but if u read
the previous paragraph, u'll understand why it didn't contrary to
what is explained in the quoted sentence above.
