March 12th, 2015.
The purpose of writing a lab report is to provide a blueprint for another scientist to repeat your experiment and get the same results.
A COPY OF THIS DOCUMENT incl. the finished PRE-LAB SECTIONis due on FORMAL LAB DAY!
Written work should never be copied from other groups. Use your own words!
Read skills section in back of text. Make sure you are familiar with using a graduated cylinder and an electronic balance and how to write a lab report (see class website) and how to draw and label diagrams. Required Lab sections-headings are underlined in red below
-see helpful hints section below, anchor chart, section descriptions & rubric for extra help
Title Page- see in helpful hints section immediately following this outline
Identifying Substances Using Density
DUE DATE: March 12th, 2015.
Combine the following two thoughts into one sentence in the past passive tense.
-To find the mass and the volume of the sample liquids.
-To use density calculations to identify the unknown liquids.
: For more help see in helpful hints section for content suggestions further on in this document. Note: No pre-lab printed on the day of the formal lab means a mark of (0) for the entire lab.
(Pre lab sections should include the following:)
must be re-written in one complete “If >>>>Then>>>>>” sentence.
Hint: Look at these two sentences and re-word them properly into one sentence;
-The densities of the unknown liquids can be compared with the known densities of the three unknown samples.
-The unknown densities can be calculated if experimental measurements are made of Mass and Volume.
_ Samples of labelled: liquids A, B and C. (pretend as unknown in this part of the lab)
_ Electronic Balance (include make or model, accuracy 0.0 g)
_ Graduated cylinders (include type material, size, accuracy 0.0 ml)
Create your own procedure
. Your procedure must be in your own words in the past,
3rd person (passive) tense and must be given in numbered steps.
Include when and where you are recording your data. Be specific. (i.e. give the table number)
Level 4 in this lab is seven numbered steps.
Include only steps that may affect results and calculations.
(i.e. do not include cleanup as it does not affect the results)
rocedure Hints and Reminders:
● Check in with PRE-LAB for your teacher before beginning.
No pre-lab = ZERO!
● Each lab group will obtain the mass and volume measurement for all of the unknown liquids and calculate their densities.
● Take all measurements to one decimal place but all density calculations to two decimal places
Pre-mass graduated cylinder each time and record this before pouring a new sample
● (Subtract initial mass from final mass to find mass of your sample).
● Do not assume each GC is the same mass. They are not!
● Read meniscus to get volume in GC.
● Zero/Tare the scale before each use
● Volumes of samples must not be more than 6 ml but they do not have to be the same
● volume each time and do not have to be exactly 5 ml. In fact they should not be exactly 5 ml.
● Keep scales at centre of bench do not move them around, they must be reset before each use
● Make sure every member of your team takes at least one reading on both g.c. and scale
● Do not return samples to original beakers after use. Pour waste in waste beakers at the back.
● Start with (A) first, (B) second and (C) third
● When each group is done . . . have one person from each group give their measurements to your teacher on the class sheet. A copy of all the class data will be posted on website.
Lab Day Check Out- With Your Teacher DO NOT INCLUDE THIS IN PROCEDURE STEPS
DO NOT BEGIN CLEAN UP UNTIL I HAVE CHECKED YOUR DATA!!!
● A group must check out together only after clean ups are completed and data…