ELN Prelab for ΔHf (MgO)
Revised: 5/30/14
Preparing the ELN for Exp #1
Go to the eResources webpage and click on LabArchives (ELN). Read watch the podcast and
thoroughly read the directions on how to use the ELN.
Filling out your SDS folder:
1. Search for “MSDS hydrochloric acid” in your web browser. Find a safety data sheet for HCl
that is a PDF. Here is an example that you can use:
http://www.sciencelab.com/msds.php?msdsId=9924285
2. Save the PDF on your computer.
3. In the ELN, on the left hand side of the screen find the SDS folder and click on “Add new
item” and then choose “Add New Page”. Name the page “HCl”.
4. In the middle of the new page, click on Attachment in the Entry Editor toolbar and attach the
SDS pdf for HCl.
5. Repeat this process with MgO, Mg, and NaHCO3. Make a new page for each of the
chemicals.
Starting your notebook:
6. Experiment Title: Click on the Expt 1 folder in the Notebook Navigator, click on “Add new
item” and then choose “Add New Page”. Name the page “Pre/In Lab”.
Objective: On the Entry Editor Toolbar, click on Heading, and type Objectives. Click “Save to
page.” Click on Rich Text. Type this into the box:
“The goal of this experiment is to find the enthalpy of formation of magnesium oxide:
Mg + ½ O2 à MgO
∆Hf = ?
Because this value is too energetic to be measured directly, Hess’ Law will be employed to
sum up 3 individual reactions to provide the overall reaction above. Constant pressure
calorimetry (qrxn = -(mCp∆T)surrounding) will be used to find the enthalpies of reaction for two
of the individual reactions.”
The delta sign (∆) is under the special character menu:
done.
. Click “save to page” once you are
ELN Prelab for ΔHf (MgO)
Revised: 5/30/14
Chemicals, Equipment, and Table of Physical Constants:
1. Click on Heading again, type Equipment & Chemical Tables. Click “save to page” Click
on Rich Text. Create tables by clicking on
. Set the table to have 8 rows and 2
columns. Click Okay.
2. In the first row of the column on the right, type “Equipment Description” in boldface. In
the cells beneath this heading, type “LabQuest2 & computer, temperature probe, 250 mL
volumetric flask, 25 mL volumetric pipet, 1L beaker, graduated cylinder, pH paper, and
calorimeter: stirrer/hotplate, ring stand, Styrofoam cup, 1L beaker, & stir bar.”
3. In the first row of the column on the left, type “Equipment Image” in boldface. You can
insert images from the internet that correspond to the description to the left in the same
row. Images should be sized on the page to be no more than 2 inches in width or length.
Any images should be properly labelled with a number and then cited in a numbered list
beneath the table. It is acceptable to take a screenshot of an image in the lab manual as
long as the web address of the document the image can from is properly cited. Save
common images and their web addresses, you will use them multiple times.
4. Click “save to page”. The table and footnotes should look like the image on the
following page.
5. On the Entry Editor Toolbar, click Sketch and draw in a calorimeter. It looks something
like this:
In the box labeled Describe this sketch, label the sketch “Calorimeter Set Up, Equipment
Image #7.” Click “save to page.”
ELN Prelab for ΔHf (MgO)
Revised: 5/30/14
ELN Prelab for ΔHf (MgO)
6. Click on Rich Text. Create tables by clicking on
Revised: 5/30/14
. Set the table to have 7 rows, 4
columns. Click Okay. Highlight the first row, right click to reveal a menu, select cell
followed by merge cell.
7. Fill out the table so that it looks like this:
Fire Diamonds can be created using a widget. Take a screen shot of the widget image
and insert it in the table. Or a screen shot the fire diamonds in the SDS files that you
saved earlier can be used. Attach the image file into the table by clicking on
.
Prelab Calculations: On the Entry Editor Toolbar, click on Heading, and type Dilution Plan.
Click “Save to page.” Click on Rich Text. Calculate how to prepare 250.00 mL of approximately
1.0 M HCl solution from the 2.5 M HCl solution. Show your work.