Calorimetry Calculation Tips

Calorimetry Calculation TipsStudents working on their Chemistry Calorimetry problems 1 and 2 should have a strong understanding of the principles behind the calculation. There are a number of ways to do this and one approach is to do the experiment step by step to help you with your calculations.When you add carbon dioxide into a container, the gas forms an equilibrium that balances the mass of the air with the mass of the gas. The gas expands, so the air has to absorb a smaller amount of gas to equalize the two masses. The net force of the expanding and contracting gases equals the force of gravity plus the displacement between the pressure of the gas and the surrounding atmosphere.When you combine all of these things in your calculations, it is time to do a little calculus to make the value of the displacement a bit easier to visualize. Let's take this simple example. Say we know the rate at which the gas has been expanding for an hour before the addition of the gas. We can put thi s in our equations to come up with the displacement.For an hour after adding the gas, the gas will expand more rapidly and will push the atmosphere out of the way, allowing for more air to enter. In order to find this we would divide the value of the displacement by the time and then multiply by the rate of the gas' expansion. We will probably know how fast the gas is expanding based on how much it weighs. Divide the mass of the gas into the mass of the atmosphere and then plug those numbers into our equation for the volume.In some cases, you might need to know something about the strength of the gas before you know the displacement. In those cases, you would multiply the density of the gas by the coefficient of the gas, which is usually the same as the volume. Again, you would divide the mass of the gas into the mass of the atmosphere and multiply the equation for the volume by the density to get the displacement. You can do some more math to determine the remainder of the relation ship but we are looking for a convenient way to make it easier to see the answer.Now that you know the answer to the displacement equation, you can plug it into the second part of the calculation and come up with your final answer. You also need to know how long the gas has been in the container. To do this, we would multiply the equation for the displacement by the time and then divide by the time to get the time.The third calculation involves an indication of the density of the gas. First, you need to know the density of the gas so that you can use the density of the gas (number of molecules per cubic centimeter) and then multiply that number by the volume to get the density. Then, we need to figure out how much the gas weighs. If you know the weight of the gas in grams, then multiply by the volume to get the density.The calculations needed to solve the Calorimetry problems 1 and 2 will give you the correct values for the displacement. This information should be part of your class ware in college, as students in the course will use these techniques and become more adept at using calculus in many situations.