Let’s say for the sake a’ argument that you’re workin’ in a 
lab—y’know, one a’ those classic chemistry labs, with bubblin’ beakers 
’n’ fume hoods ’n’ white-lab-coatted science guys wearin’ goggles ’n’ 
stuff—an’ ya need to measure out 100mL a’ ... let’s say hydrofluoric 
acid?
Now, ya don’t need to be so exact as to use a fancy volumetric 
pipette or flask, but ya DO wanna do a li’l better than your average 
run-a’-the-mill flask or beaker. So: what piece a’ lab glassware do ya reach for?
Even if ya don’t work in a fancy lab, there’s a real good chance you used one a’ these devices back in high school chemistry.