Reflection Of The Energy Change Of A Chemical Reaction

he experimental variable in this experiment was the changing number of Alka Seltzer tablets that were put into the 250mL beaker of vinegar. Some of the control variables in this experiment were that the same beaker and thermometer were used for each trial, the same type of vinegar and Alka Seltzer were used for each trial, and the same amount of vinegar. The original Hypothesis was that more Alka Seltzer would increase the temperature of the vinegar was not correct. After analyzing the data it can be seen that for the first trial the temperature did not change as it stayed at 24 degrees Celsius before and during the reaction with 1 tablet, also for trial two with two tablets the temperature stayed the same at 23 degrees Celsius and did

In order to measure the heats of reactions, add the reactants into the calorimeter and measure the difference between the initial and final temperature. The temperature difference helps us calculate the heat released or absorbed by the reaction. The equation for calorimetry is q=mc(ΔT). ΔT is the temperature change, m is the mass, c is the specific heat capacity of the solution, and q is the heat transfer. Given that the experiment is operated under constant pressure in the lab, the temperature change is due to the enthalpy of the reaction, therefore the heat of the reaction can be calculated.

This reaction is exothermic, meaning it releases heat when reactants are converted into products. The negative change in enthalpy (∆H° = -36,757 J) for this reaction indicates that the reaction is losing heat to its surroundings.

For q, you found how much heat was gained by the water so you know that same amount of heat was lost by the metal. Therefore, qmetal = -qwater. The mass of the sample was recorded from the baggie. The temperature change

2. How did concentration and/or volume differences affect the heat change (q) for each trial?

We can assume that the specific heat capacity of water is 4.18 J / (g × °C) and the density of water is 1.00 g/mL.

In part I, the ΔH of each individual reaction was obtained by performing each reaction inside a calorimeter. Temperature probes were inserted in the calorimeter and ΔT was measured. By using the equation q = Msol’n x Cp x ΔT + Ccal x ΔT, the heat absorbed by the surroundings, q, was obtained for each reaction. The negatives of these values, or heat released by the

Exothermic reactions transfer energy to the surroundings. The energy is usually transferred as heat energy, causing the reaction mixture and its surroundings to become hotter. The temperature increase can be detected using a thermometer. Some examples of exothermic reactions are:

Chemical reactions that release energy are called exothermic reactions, these reactions are observed by an increase in temperature of the reaction mixture.

The lab used methods of calorimetry in order to measure the temperature change of reactions and calculate the changes in

We will be using 6 different fuels to heat up 100ml of water, and find out the changes of the temperature. We will measure the temperatures of the water before and after the experiment. We will burn heat the water for exactly 2 minutes, and check the changes in temperature. The change in temperature will allow us to work out the energy given off the fuel by using this formula:

Introduction: The theory behind this experiment is the heat of a reaction (∆E) plus the work (W) done by a reaction is equal to

3. Calculate the total heat released in each reaction, assuming that the specific heat of the solution is the same as for pure water (4.18J/gK). Use q=mcΔT. Show work here and record your answer in Data Table 2.

Purpose: This lab taught procedures for determining heat of capacity of a calorimeter and measuring enthalpy of change for three reactions. It also enforced methods of analyzing data obtained through experimentation and calculating enthalpy. These procedures are used in the branch of thermodynamics known as thermochemistry which is the study of energy changes that accompany chemical reactions. Concepts from this lab can be used to determine the potential energy of a chemical reaction. Much of the energy people depend on comes from chemical reactions. For example, energy can be obtained by burning fuel, metabolizing of food or discharging a batter.

Purpose: You will determine the molar heat of neutralization of 1.00 M HCL and 1.00 M NaOH in Kilojoules.