# If I did an experiment investigating which sugar caused yeast to respire more and for glucose my starting height was 23 and my ending height was 27...after 15 minutes. How do I calculate the...

If I did an experiment investigating which sugar caused yeast to respire more and for glucose my starting height was 23 and my ending height was 27...

after 15 minutes. How do I calculate the volume change?

### 1 Answer | Add Yours

I am assuming that you set up several yeast fermentations using different sugars in each separate batch and measured the height of the foam formed on top using a ruler (or perhaps the amount of CO2 produced directly by measuring water displaced). Assuming that you are running each fermentation in the same shape and type of vessel then it wouldn't even be neccessary to calculate the volume since the relative measurements of the heights would be enough to compare the sugars against each other (the greater the height the greater the volume no matter what the shape). But if you want to measure the volume anyway than the answer is that it depends greatly on the shape of the experimental setup. If the foam or gas is rising up a cylinder and the height of the cylinder is being measured then the area would be A=h*pi*r^2 where h is the height and r is the radius of the base circle. Other shapes use other equations to measure the area.

**Sources:**