Surface tension of a fluid to sustain a certain gauge pressure within a bubble

Question

What is the minimum surface tension of a fluid that can sustain a gauge pressure of 0.1 kPa in a 0.5 cm radius bubble?

Answer 1

So the extra pressure between the inside and outside of the bubble will be the gauge pressure. So the gauge pressure is caused by the surface tension of the bubble. This is known as the Young-Laplace equation:

ΔP =4 γ/R where γ is hte surface tension. So γ = RΔP/4 where R is in m, ΔP in Pascals and γ in Pa-m or kg/s²