Science Buddies: "Ask an Expert"

If I want to find out the temperature of the container or surrundings during a reaction between vinegar oand baking powder, where should I keep the bulb of the thermometer? In the solution or in air just above the solution?

Are you trying to measure if heat is given off during the vinegar/baking soda reaction? i.e. - Is it exothermic?

One device that is commonly used for this type of measurement is called a calorimeter and is very easy to construct from Styrofoam cups. It might be interesting to measure the temperature in the solution as well as inside the wall of a calorimeter to measure the heat given off. Measuring the air just above the solution is less accurate because it could be affected by air currents and how the heat dissipates off the solution.

Good luck!

Audrey

Hello Audrey,
Ah, actually, the reaction is endothermic reaction so, heat is absorbed by the reactants from the surroundings. I want to measure that how much effect does this change in heat energy bring onto the temperature of the surroundings. Maybe, you are saying that I should place the calorimeter inside the wall of the container.

Huzaifa.

Hi Hazaifaf,

You are correct that the temperature of the vinegar solution goes down when baking soda reacts with vinegar. This activity from the American Chemical Society describes how to measure the temperature change in this reaction:

http://www.inquiryinaction.org/classroo ... .php?id=24

Note that you will measure the temperature change more accurately if you do the experiment in an insulated foam cup, with a foam cover on top of it, with the thermometer poking down into the solution through a hole in the cover.