Mass & Volume Lab:Mass & Volume Lab:Measuring VolumeMeasuring Volume

We are making new groupsWe are making new groups Take out your lab notebooks. Write Take out your lab notebooks. Write

the DQ: How does the volume of a the DQ: How does the volume of a substance relate to its mass?substance relate to its mass?

Go to the lab stationsGo to the lab stations Discuss at least two ways to measure Discuss at least two ways to measure

the volume of the metal cylinders at the volume of the metal cylinders at your lab stationyour lab station

Record notes in your lab notebook.Record notes in your lab notebook.

Mass & Volume LabMass & Volume Lab

Causal Question: How do measures Causal Question: How do measures of mass and volume relate to one of mass and volume relate to one another?another?

Mass & Volume LabMass & Volume Lab In your lab notebooks, complete the following:In your lab notebooks, complete the following:

Problem Statement/Research QuestionProblem Statement/Research Question Give a prediction for your experiment (graph)Give a prediction for your experiment (graph) Experimental DesignExperimental Design

Identify the IV (Volume) Identify the IV (Volume) Identify the DV (Mass)Identify the DV (Mass) State what variables you will attempt to keep State what variables you will attempt to keep

constant during your tests.constant during your tests.

Experimental MethodExperimental Method List/bullet steps needed to measure your List/bullet steps needed to measure your

independent and dependent variables.independent and dependent variables.

8/13/158/13/15 Place Unit 1A HW Packet in the Place Unit 1A HW Packet in the

basketbasket Period 2 – Turn in your citizenship Period 2 – Turn in your citizenship

paper and health info paper, if you paper and health info paper, if you have not yet done thathave not yet done that

Go to the lab station and work on Go to the lab station and work on your procedures for the mass and your procedures for the mass and volume lab.volume lab.

Mass & Volume LabMass & Volume Lab Data Collection (take notes as you conduct Data Collection (take notes as you conduct

the experiment)the experiment) Collect quantitative data in an Collect quantitative data in an appropriate appropriate

tabletable Qualitative data underneath your table:Qualitative data underneath your table:

Notes on procedural stepsNotes on procedural steps, materials , materials actually used for measuring mass & volume actually used for measuring mass & volume of assigned objects. of assigned objects.

Relevant Relevant ObservationsObservations made during data made during data collectioncollection

Record data in class data table when Record data in class data table when done…done…

Mass & Volume Post-LabMass & Volume Post-Lab Using LabQuest, plot class data for your Using LabQuest, plot class data for your

metal type (orange or shiny).metal type (orange or shiny). Whiteboard a Whiteboard a sketchsketch of your plot. of your plot.

Sketch graphs = label units on axes, Sketch graphs = label units on axes, sketch in the trend (you do not need #’s sketch in the trend (you do not need #’s on axes, points don’t need to be exact)on axes, points don’t need to be exact)

Write the equation of the line (curve) with Write the equation of the line (curve) with correct variables and unitscorrect variables and units

i.e. relax there perfectionists!i.e. relax there perfectionists!

Graph Info for Labs:Graph Info for Labs:

In your lab book:In your lab book: Sketch the graph (title, labeled axes, general Sketch the graph (title, labeled axes, general

trend shown)trend shown) Write equation describing linear fit (substitute Write equation describing linear fit (substitute

appropriate variables and include units for slope appropriate variables and include units for slope and y-intercept)and y-intercept)

For Lab Report:For Lab Report: Autoscale graph from Zero (0,0 origin)Autoscale graph from Zero (0,0 origin) Check point protectors in graph optionsCheck point protectors in graph options Uncheck connect points in graph optionsUncheck connect points in graph options Copy and paste graph to a Word Document and Copy and paste graph to a Word Document and

SaveSave

Discussion PointsDiscussion Points

How would you describe the relationship How would you describe the relationship between these two variables?between these two variables?

What is the What is the physicalphysical meaning of the meaning of the slope? What are the units for slope?slope? What are the units for slope?

Should this metal always have the same Should this metal always have the same slope?slope?

What are the units for the y-intercept?What are the units for the y-intercept? Theoretically, should there be a y-Theoretically, should there be a y-

intercept? If not, why is there a y-intercept? If not, why is there a y-intercept?intercept?

Linear equations for Scientific Linear equations for Scientific plots:plots:

1.1. Start with generic y = m x + b Start with generic y = m x + b

2.2. Replace y, and x with chemistry Replace y, and x with chemistry variables from the graph axes; variables from the graph axes; replace m and b with values from replace m and b with values from analysis of graph for slope and analysis of graph for slope and intercept.intercept.

What are the numbers missing?What are the numbers missing? Add Units!!!Add Units!!!

Linear equations for Scientific Linear equations for Scientific plots:plots:

3.3. Decide if b (y-intercept) is significant:Decide if b (y-intercept) is significant: 5% Test:5% Test:

(Y-max = largest y value from data table)(Y-max = largest y value from data table) Rule: if intercept is less than or = 5% of max Y Rule: if intercept is less than or = 5% of max Y

value, the intercept is negligible and you may value, the intercept is negligible and you may drop it from the equation; drop it from the equation;

if intercept is greater than 5% of max Y value, it is if intercept is greater than 5% of max Y value, it is significant and you must keep it as part of the significant and you must keep it as part of the final equation. final equation.

4.4. Write the final equation of the lineWrite the final equation of the line

%100max

Y

b

Percent ErrorPercent Error

How far off the results are from the How far off the results are from the actual valueactual value

Percent error = Percent error = |observed – actual| |observed – actual| X X 100100

actualactual

Mass & Volume ReportMass & Volume Report

Experimental BackgroundExperimental Background Complete all sectionsComplete all sections

Apparatus and Method sections:Apparatus and Method sections: Include materials.Include materials. Labeled apparatus sketch in inkLabeled apparatus sketch in ink Detailed procedures, as developed and Detailed procedures, as developed and

used by your group (include any used by your group (include any refinements)refinements)

Mass & Volume ReportMass & Volume Report Data Collection:Data Collection:

Include Quantitative data you took as a group (RAW Include Quantitative data you took as a group (RAW data).data).

Include Qualitative dataInclude Qualitative data Use titles and headings! (include units and Use titles and headings! (include units and

uncertainty)uncertainty) Precision will be checked for.Precision will be checked for.

Data Processing Data Processing Table with class data (indicated in title) for your Table with class data (indicated in title) for your

metal onlymetal only Graph class data of only your metal (not both)Graph class data of only your metal (not both) Line of best fitLine of best fit Include equation under the graph and discuss it in Include equation under the graph and discuss it in

the conclusion.the conclusion. % error calculation% error calculation

Mass & Volume ReportMass & Volume Report

ConclusionConclusion Make conclusions based on results. (i.e. Make conclusions based on results. (i.e.

what trend does the graph show? What what trend does the graph show? What relationship exists? How was it relationship exists? How was it modeled?)modeled?)

Explanation/Justification: What does the Explanation/Justification: What does the slope of the line mean? What is it slope of the line mean? What is it called? Was your slope value too high? called? Was your slope value too high? Too low? Explain!Too low? Explain!

Mass & Volume ReportMass & Volume Report

Evaluation (very important!) – make Evaluation (very important!) – make twotwo paragraphs following the paragraphs following the conclusionsconclusions Identify the limitations of the procedures Identify the limitations of the procedures

and materialsand materials Discuss how these limitations affect the Discuss how these limitations affect the

resultsresults How could these things be improved to How could these things be improved to

better the experiment?better the experiment?