Science Buddies: "Ask an Expert"

Hello!
We are finished with our growing rock candy project. Unfortunately the rock candy crystals are stuck to the bottom of the jar so we cannot pull the string out to measure to see which one is bigger. Can you offer any other suggestions on how to confirm which one grew better, aside from just observation. Would weighing the jars be acceptable way? This is for a school science fair project. Thank you so much!

Hello,

This sounds like a fun project! Weighing the jars could work after pouring out the sugar-water solution. Since the weight of each jar might vary slightly, I'd suggest labeling each jar and weighing the combined crystal + jar. Then clean out the jars and reweigh the empty jars and subtract the weight of each jar from the corresponding combined crystal + jar weight to calculate the weight of each crystal.

Alternatively, you might be able to loosen the crystals from the bottom of the jar by heating the bottom of the jar (hot water maybe?) to melt a thin layer of sugar without damaging the shape of the crystal too much to still allow for measuring the length and the width.

Good luck!

Audrey

thank you!