Determinaing Enthalpy Change of Potassium

These values can be determined from a reaction table ('ICE' table), as shown in Table 1:

the reaction did not match the slope of the data trend before the reaction, using the equations of

    One possible source of error that can affect the results was that a mercury thermometer was used instead of an electronic one. The use of a mercury

Weight 10 dry post-82 pennies which get 77.12g, using 30ml initial volume measuring the volume of 10 pennies, record the data 9.1ml. Using equation Density= Mass/Volume, get the density of the pre-82 pennies is 8.47g/ml. Then calculate the error%=0.04%, and the deviation%=7.13%.

There were three different runs in order to have comparable data and to increase the validity of the experiment. The first run gave 39% of Sodium Bicarbonate. The second run gave 34% of Sodium Bicarbonate while the third one gave 39%, which is the same as the first run. The average percentage was 37% which is much lower than the manufacturer's percentage of 59%. The percent error came out to be -37%.

The first part of this lab’s objective was to find the calorimeter constant using DI water. We accomplished this by first checking the temperature and then adding 20 mL of cold DI water into our calorimeter. Next we collected 20 more mL of DI water in a 50 mL beaker and placed it onto a burner in order to heat it. We removed the beaker once the temperature of the water reached 60º celsius. After we removed the water, we poured it into the calorimeter with the cold water and took the temperature. The temperature ended up being 37º celsius. From this information we were able to calculate for qhot, qcold, qcal and Ccal. To be as accurate as possible we conducted this same test three more times and used the averages from all Ccal calculations as the final Ccal.

Experiment 2 focused on finding the enthalpy of solution of magnesium chloride. Testing the enthalpy of solution started with measuring out 10 mL of deionized water in a graduated cylinder for three separate trials, each trial having a different mass of magnesium chloride. The water was then poured into a well of a Styrofoam calorimeter then the initial temperature of water was taken using a temperature probe and the LoggerPro programming. A measured amount of magnesium chloride was placed in the same well as the water in the calorimeter,

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.

formula Kw[Fex(C2O4)y]·zH2O. The variables x, y, and z were determined through the duration of the

Even though the result of an experiment is accurate and matches the literature value, it does not mean that there were no mistakes made. As the difference of the percentage uncertainty and the percentage error suggests there were random errors made. First of them was the heat energy lost to the surrounding environment during the experiment process taking place. This caused the recorded highest temperature to be smaller than the actual highest temperature that was meant to reach. This could have been prevented by adding in more and perfect

Stoichiometry has many uses in the real world. In the chemical industry and in professional scientific experiments, scientists use stoichiometry to save money. Scientists use stoichiometric calculations to determine the amount of a substance they need to purchase for a specific reaction. There are four possible reactions that can occur when sodium bicarbonate thermally decomposes. In this lab, stoichiometry was used to find out which balanced chemical equation out the four best represents the thermal decomposition of sodium bicarbonate.

From the calculation (See Appendix I), we get the 3-sigma control limits for the process, i.e. UCL=0.091, LCL=0.014. These control limits indicate that if the error proportion is within the range of [0.014, 0.091], the process is under control; if not, the process is out of control.

This experiment was performed to determine the heat of neutralization between Hydrogen chloride (HCl) and Sodium hydroxide (NaOH). A temperature probe was used to measure the temperature of the reaction when the base (NaOH) was poured into the acid (HCl). The data was collected on logged on LoggerPro.

Purpose: To measure the heats of reaction for three related exothermic reactions and to verify Hess’s Law of Heat Summation.

And copper (II) ions were reduced to copper because it gained electrons and its oxidation number changed from +2 in copper (II) ions to 0 in copper.