formal lab report 2 - calorimetry | Mole (Unit) | Heat Capacity

 

calorimetry lab report

SAMPLE INFORMAL LAB REPORT FROM CHEMISTRY Title: Determination of Heat Capacity. Introduction: The purpose of this experiment was to determine the heat capacity of an adiabatic calorimeter. An adiabatic calorimeter is an apparatus used to measure heat changes for experiments done at constant pressure. CALORIMETRY – EXPERIMENT A ENTHALPY OF FORMATION OF MAGNESIUM OXIDE INTRODUCTION This experiment has three primary objectives: 1. Find the heat capacity (Cp) of a calorimeter and contents (calibration). In the first lab period, the data to determine the enthalpy of reaction for Mg + HCl and MgO + HCl will be collected (one trial on each. Experiment 6 Coffee-cup Calorimetry Introduction: Chemical reactions involve the release or consumption of energy, usually in the form of harlanpds.gq is measured in the energy units, Joules (J), defined as 1 kg⋅m2/s2. Another common heat unit is the calorie (cal). It .


Lab 4 - Calorimetry


Abstract: In Part I, the specific heat of an unknown metal, lead, was calculated to be 0. Introduction: For Part I, the objective was to calculate the specific heat of an unknown metal. Specific heat is the amount of heat needed to raise the temperature of one gram of [a pure substance] by one degree either Celsius or kelvin.

It is a rearrangement of the following equation, calorimetry lab report, the standard calorimetry lab report for calculating the heat transfer in a reaction: 2. Once the specific heat of the unknown metal has been calculated, its identity will be determined using the following table of common metals and their specific heats provided by Hamilton et al. In Part I of this experiment, the metal is considered the system and the calorimeter calorimetry lab report considered the surroundings.

Ideally, the surroundings account for the entire universe minus the systemcalorimetry lab report in this case, the calorimeter is assumed to insulate the heat exchange completely and is also assumed to not take in any heat. Thus, in our calculations, only the water contained in the calorimeter is used to calculate the value of heat transfer. The following equation provided calorimetry lab report Hamilton et al.

This equation is very important because it is not possible to determine the heat of the system directly. However, the heat of the surroundings is able to be calculated, so it is very important to be able to relate the heat of the surroundings to the heat of the system.

In Part II, the objective is to find the molar heat of neutralization of hydrochloric acid for the following reaction1: 4. The molar heat of reaction is found by first calculating the heat of reaction, the heat transferred during a certain chemical reaction.

The heat of reaction is an extensive property because its value is reliant on the amount of limiting reactant used in the reaction. Molar heat of reaction is, however, an intensive property because it is instead the amount of heat produced per mole of a certain reactant, thus can be calculated independently of reactant amount. Hamilton et al. Discussion of Results: The table below contains the results of the above calculations and the data through which calorimetry lab report average specific heat of unknown metal and the average molar heat of neutralization were found.

In Part I of this experiment, the heat exchange between the unknown metal sample and a measured amount of water in an insulated coffee-cup calorimeter was observed and measured in order to find its specific heat.

The amount of heat transferred to the water was calculated from its mass, specific heat, and temperature change. From the metals mass, temperature change, and heat exchange, the specific heat was calculated to be 0.

Thus, the average of both trials was 0. Of the metals listed on the table provided by Hamilton et al. Lead is a metallic, calorimetry lab report metal, whereas tungsten is a lustrous. The unknown metal was described as grey, round pellets, calorimetry lab report, thus the identity of the unknown metal must be lead.

In Part II of the experiment, molar heat of neutralization of hydrochloric acid was calculated by first determining the heat of the neutralization reaction between measured amounts of hydrochloric acid and sodium hydroxide, calorimetry lab report.

Using the mass of solution after mixing calculated calorimetry lab report the final volume and density of waterits specific heat, and temperature change, the heat released by the reaction was found. After converting that heat calorimetry lab report kilojoules and calculating the moles of hydrochloric acid used in the reaction, the molar heat of neutralization in kilojoules per mole of hydrochloric acid was obtained. The results from both parts of the experiment were close to the accepted values of leads specific heat and hydrochloric acids molar heat of neutralization, respectively.

There was, however, a limitation issue in Part I because the calculated T was very small. The small T allowed for only one significant figure in the calculations, even though the measuring device should have allowed for two.

A solution to this issue would be to measure a greater T by using either a larger amount of lead or a smaller amount of water in the experiment. The T will then carry two significant figures and no longer hinder the calculations, calorimetry lab report. An area where an error could have been introduced during the experiment was in transferring the metal from Part I from the boiling water to the calorimeter.

It was exposed to the air for about three seconds before being safely contained within the Styrofoam. It is likely that some heat escaped to the air, not to the water to be measured. The final temperature would have been too low and forced the calculations off, making the experimental specific heat to be too low, calorimetry lab report.

A second area where error could have been introduced was in Part II, when measuring the initial temperature of the solutions. If not given enough time to cool down between trials, the temperature probes may not have given accurate readings of the actual initial temperatures of the reactants.

The low T will translate to a low heat of reaction. This would skew the calculations based on equation 5 to yield a low experimental molar heat of neutralization of HCl because the low value will be in the numerator. Conclusion: In Part I, an unknown metal lead was identified by its specific heat, 0. References: 1. Hamilton, P, calorimetry lab report. Yau, C. Answers to Post-Lab questions: 1. Examine the initial and final temperatures in Part I.

Explain how the temperatures tell you what type of reaction was involved endothermic or exothermic. Are the signs of your qwater and qmetal consistent with this? We measured the final temperature within the calorimeter, and it was higher than the initial temperature, indicating an exothermic reaction, calorimetry lab report. However, the reaction here is a physical exchange of heat, not a chemical reaction, therefore there was no endothermic or exothermic reaction involved.

In Part I, we see that copper and zinc have the same specific heat See table in the Introduction. If you obtained an experimental value of 0. We recorded the appearance calorimetry lab report the unknown metal, as well as determining its specific heat. If the metal was a silvery-grey, then we could assume that the metal was zinc. If the metal was a coppery color, then we could assume that the metal was copper. We will not base our conclusion on only specific heat.

We assumed that no heat is lost to the surroundings beyond the nested coffee cups, calorimetry lab report. In Part I, obviously there would have been some loss in heat calorimetry lab report the hot metal is transferred to the calorimeter. How does that unavoidable heat loss affect your calculated specific heat of the metal?

Would your calculated calorimetry lab report heat be too high or too low due to this error? Explain fully. The calculated specific heat would calorimetry lab report too low due to this error.

The calculated change in temperature for the water and the calculated transferred heat would be too low and the calculated change in temperature for the metal would be too high. For example, in an unknown metal experiment, the final temperature was First, the change in temperature for water will calorimetry lab report calculated to be too low. Correct calculations of Twater: Incorrect calculations of Twater:.

Third, the heat transfer value is still incorrect. Fourth, the change in temperature for the metal will be calculated to be too high. Fifth, the specific heat of the metal is calculated to be too low. Correct calculations of smetal: Incorrect calculations of smetal:. In Part II, we assume that the density and specific heat calorimetry lab report the solution is the same as that of water, calorimetry lab report.

What justifications do we have to make that assumption? In Part II, the reactants, hydrochloric acid and sodium hydroxide, reacted together to form salt and water, calorimetry lab report. Both reactants were 1 M solutions, thus the amount of salt produced in neutralization compared to the water from calorimetry lab report reagents plus the water produced in the reaction is negligible.

Thus, the final solution is mainly composed of water or dilute, and we can assume that the density and specific heat of the solution are the same as that of water. Calorimetry lab report the molar heat of neutralization obtained in your experiment assuming it is. Show your calculations, calorimetry lab report. Hint: How many moles of HCl are involved? In the proposed experiment, there would be the same number of moles of hydrochloric acid as of sodium hydroxide, calorimetry lab report.

Since, in equation 4the two reactants have a stoichiometric relationship ofthere is no limiting reagent to worry about.

Read Free For 30 Days. Uploaded by api Flag for inappropriate content. Related titles. Carousel Previous Carousel Next. Jump to Page, calorimetry lab report. Search inside document. Table 3. Results for Part I and II In Part I of this experiment, the heat exchange between the unknown metal sample and a measured amount of water in an insulated coffee-cup calorimeter was observed and measured in order to find its specific heat. Correct calculations of Twater: Incorrect calculations of Twater: Correct calculations of qwater: Using the molar heat of neutralization obtained in your experiment assuming it is correctcalculate how much heat you would expect to be produced if you mixed Documents Similar To formal lab report 2 - calorimetry.

Tsamara Alifia. Bettinamae Ordiales De Mesa. Narendran Sairam. Anania Yeghikian. Burhan Riaz. Dylan Custer.

 

Calorimetry Experiment Lab Report | Sodium Hydroxide | Hydrochloric Acid

 

calorimetry lab report

 

SAMPLE INFORMAL LAB REPORT FROM CHEMISTRY Title: Determination of Heat Capacity. Introduction: The purpose of this experiment was to determine the heat capacity of an adiabatic calorimeter. An adiabatic calorimeter is an apparatus used to measure heat changes for experiments done at constant pressure. Experiment 6 Coffee-cup Calorimetry Introduction: Chemical reactions involve the release or consumption of energy, usually in the form of harlanpds.gq is measured in the energy units, Joules (J), defined as 1 kg⋅m2/s2. Another common heat unit is the calorie (cal). It . Calorimetry is the measurement of heat transfer. In this experiment, we used two stacked Styrofoam coffee cups to make an insulated container called a calorimeter. These cups minimize the exchange of heat between what is inside of it and what is outside it, or its surroundings. When heat (q) flows in and out of a substance, the temperature changes based on the substance’s mass in grams and 82%(34).