Students in Antonia Ciccarelli’s physical science class did a pretty cool experiment to show the effect of particle size on the rate of a chemical reaction. Everyone was goggled up as they measured out their sodium bicarbonate/citric acid pieces – also known as Alka Seltzer – and water.

 

 

They broke the tablets into different size pieces and made their hypothesis regarding size of tablet with amount of liquid. Then they put their tablets and water into sealed film canisters, turned them upside down on a tray and timed how long it would take for the canister to explode. Mixing the sodium bicarbonate/citric acid with water causes a chemical reaction, producing a gas.

 

 

Sure enough, the canisters were popping! And, as many of the students hypothesized, the larger pieces of tablet in the canister caused the chemical reaction to happen quicker than smaller pieces.

 

 

After doing the experiment three different times with each particle size, the students calculated their average time, provided their evidence and then rewrote their hypothesis, if needed.

 

Here is a very quick video Ms. Ciccarelli captured of the big moment.