02 May WHAT IS THE HEAT ENERGY OF THE CALORIMETER?
Procedures Experiment 1: Measuring the Calorimeter Constant The calorimeter constant can be measured by combining cold and hot water in the calorimeter and comparing the actual final temperature with the expected final temperature. 1. Take an Erlenmeyer flask from the Containers shelf and place it on the workbench. 2. Take a constant temperature bath from the Instruments shelf and place it on the workbench. Set the bath to 60 �C. 3. Take a thermometer from the Instruments shelf and attach it to the flask. 4. Fill the flask with 50 mL water from the Materials shelf and place the flask in the constant temperature bath. 5. While the water is heating in the bath, take a calorimeter from the Containers shelf and place it on the workbench. 6. Fill the calorimeter with 50 mL water. 7. Attach a thermometer to the calorimeter and record the temperature in your Lab Notes. 21.5C 8. When the temperature of the water in the Erlenmeyer flask reaches 60 �C, remove the thermometer from the flask, drag and drop the flask onto the calorimeter and select the Pour All option. 9. Record the temperature of the liquids combined in the calorimeter. 40.3C 10. When you are finished, discard everything in the recycling bin beneath the workbench. Experiment 2: Enthalpy Change of a Chemical Reaction 1. Take another calorimeter from the Containers shelf and place it on the workbench. 2. Take a balance from the Instruments shelf and place it on the workbench. Place the calorimeter directly on it to weigh it. Record the mass of the empty calorimeter in your Lab Notes. Place the calorimeter back on the workbench. 18.6 g 3. Attach a thermometer to the calorimeter. Record the temperature. 21.5C 4. Add 50 mL of 1.0 M hydrochloric acid (HCl) to the calorimeter. 5. Add 0.15 g of magnesium (Mg) to the calorimeter. 6. Watch the thermometer and record the maximum temperature displayed by the thermometer. 30.7C 7. Measure and record the mass of the calorimeter and its contents on the balance as Trial 1. Place the calorimeter in the recycling bin. Trial 1-68.970g 8. Trial 2: Repeat steps 1 – 7 with a new calorimeter, using 50 mL of hydrochloric acid (HCl) and 0.25 g of magnesium (Mg). Record the maximum temperature displayed by the thermometer in the calorimeter. 36.8C Trial 2-69.062g 9. Trial 3: Repeat steps 1 – 7 with a new calorimeter, using 50 mL of hydrochloric acid (HCl) and 0.35 g of magnesium (Mg). Record the maximum temperature displayed by the thermometer in the calorimeter. 42.9C Trial 3-69.153g The Enthalpy Change of a Chemical Reaction Experiment 1 1. Record the following: a. Initial temperature in the calorimeter (C): 21.5C b. Maximum temperature in the calorimeter from the reaction (C): 40.3C c. Calculate deltaT by subtracting (b) from (c) deltaT = Tinitial (C): 2. What was the initial heat energy before mixing the cold and hot water? To calculate this you need to use the formula : Qinitial = m1*Cp*T(of the hot water) + m2*Cp*T (of the cold water) where Q is the heat energy, m is the mass , Cp is the specific heat of water 4.184 J/g*C, and T is the temperature. 3. What was the final heat energy after mixing the cold and hot water? To calculate this you need to use the formula : Qfinal = (m1+m2) * Cp * Tfinal 4. What is the heat energy of the calorimeter? You can calculate the calorimeter heat energy as the difference between the initial and final heat energies. Choose the closest answer. 5. What is the calorimeter constant? You can calculate the calorimeter constant, Ccal, per degree change of the calorimeter by taking the calorimeter heat energy and dividing it by the temperature change undergone by the calorimeter: Experiment 2 1. Record the following for each of the three trials: Trial 1 a. Mass of the empty calorimeter (g): b. Initial temperature in the calorimeter (C) c. Maximum temperature in the calorimeter from the reaction (C): d. Calculate deltaT by subtracting (b) from (c) deltaT = Tmaximum – Tinitial (C): e. Mass of the calorimeter and its contents after the reaction (g): f. Calculate the mass of the contents of the calorimeter (g): e – a g. Calculate the moles of Mg reacted (MW=24.305 g/mole): Trial 2 a. Mass of the empty calorimeter (g): b. Initial temperature in the calorimeter (C): c. Maximum temperature in the calorimeter from the reaction (C): d. Calculate deltaT by subtracting (b) from (c) deltaT = Tmaximum – Tinitial (C): e. Mass of the calorimeter and its contents after the reaction (g): f. Calculate the mass of the contents of the calorimeter (g): e – a g. Calculate the moles of Mg reacted (MW=24.305 g/mole): Trial 3 a. Mass of the empty calorimeter (g): b. Initial temperature in the calorimeter (C): c. Maximum temperature in the calorimeter from the reaction (C): d. Calculate deltaT by subtracting (b) from (c) deltaT = Tmaximum – Tinitial (C): e. Mass of the calorimeter and its contents after the reaction (g): f. Calculate the mass of the contents of the calorimeter (g): e – a g. Calculate the moles of Mg reacted (MW=24.305 g/mole): 2. Calculate the heat released into the solution for the 3 reactions, according to: q(reaction)ﾠ=ﾠ Ccal * Delta T + mass(contents) * Cp (contents) * deltaT Cp is the specific heat (assume 4.18 J/goC) a. Trial 1(J) b. Trial 2 (J) c. Trial 3 (J) 3. Find the molar heat of reaction for each experiment in units of KiloJoules / (mole of Mg) by dividing the heat of reaction (converted to KJ by dividing by 1000) by the moles of Mg used. a. Trial 1KJ/mol b. Trial 2 KJ/mol c. Trial 3 KJ/mol 4. Calculate and record the average molar heat of reaction from the three results.
Our website has a team of professional writers who can help you write any of your homework. They will write your papers from scratch. We also have a team of editors just to make sure all papers are of HIGH QUALITY & PLAGIARISM FREE. To make an Order you only need to click Ask A Question and we will direct you to our Order Page at WriteDemy. Then fill Our Order Form with all your assignment instructions. Select your deadline and pay for your paper. You will get it few hours before your set deadline.
Fill in all the assignment paper details that are required in the order form with the standard information being the page count, deadline, academic level and type of paper. It is advisable to have this information at hand so that you can quickly fill in the necessary information needed in the form for the essay writer to be immediately assigned to your writing project. Make payment for the custom essay order to enable us to assign a suitable writer to your order. Payments are made through Paypal on a secured billing page. Finally, sit back and relax.
About Writedemy
We are a professional paper writing website. If you have searched a question and bumped into our website just know you are in the right place to get help in your coursework. We offer HIGH QUALITY & PLAGIARISM FREE Papers.
How It Works
To make an Order you only need to click on “Order Now” and we will direct you to our Order Page. Fill Our Order Form with all your assignment instructions. Select your deadline and pay for your paper. You will get it few hours before your set deadline.
Are there Discounts?
All new clients are eligible for 20% off in their first Order. Our payment method is safe and secure.