Week 6Unit 1 Matter (and Measurements)

Agenda

• EXP Reaction in a Bag

• Review: Sig Figs & Sci Not

• EXP Density (Modified Lab Report: Only Data, Graphing, and

Analysis

• Review: Metric System and Conversions

• Questions and Answers Session (Q/A)

Reaction in a BagExperiment – FULL Lab Report

Student Results

Part B• Create the 9 possible combinations as

CONTROL experiments to provide evidence to accept/reject hypothesis.

• Make observations.

• Reject/Accept your hypothesis.

• Answer Analysis questions to understand the data.

• C.E.R.

Results

Part B

• 9 – 10 combinations

• Divide and Conquer

Review Class Results

Evidence

Gas Temperature Change Color ChangeClick to add text

The Complete Reaction

Review & DepthSig Figs/ Sci Not

Math with Significant Figures

Addition & Subtraction Multiplication & Division

If it becomes tricky....go sci. not.

https://www.grandinetti.org/sig-fig-calculations

Scientific Notation

Math with Scientific Notation

Addition & Subtraction Multiplication & Division

EXP DensityVisually Representing and Analyzing

Quantitative Data

* What does the data tell us?*

Density

• Intensive property

• Mass of an object PER ml

• 1ml = 1 cm^3

Which has more mass?Which has more volume?

Which has a greater density?

Gathering Data

Measurements of a Liquid

Measurements of a Solid

Part A

1. Add one more row.

2. The first volume of water can be

"0".

3. Watch for significant figures

when you are reading

measurements tools AND doing

math with the measurements.

0

Add one more row here.

Part B: Solids

You will be measuring the volume of

the solid in 3 different ways.

1. Using a ruler.

2. Using the water displacement

method (1 L cylinder)

3. Using the water displacement

method with the overflow can (25 –

100 ml cylinder)

(One side)3 = Volume

The Overflow Can

Use a graduated cylinder to collect

the "overflow" that is as accurate as possible .

(between 25 ml– 100 ml)

What does the "overflow" measure?

The Math

Ultimately, you are

trying to get the mass

per ml so you can

compare different

substances/objects.

What is the unit for

density???/

Data Analysis

Water• What is the density of water?

• Besides 1 ml = 1 cc = 1 cm3, what does it also equals specifically for water?

4 Metals• What is the density of each

unknown metal?

• The results should be relatively consistent for all 3 methods of collecting volume of the metal.

• What is the identity of each unknown metal? (use the next slide)

Identify the Unknown

•Use the table to identify the unknown using YOUR data. (see the next slide for ACTUAL identities)

•If two metals have the same density, use otther

properties to make a claim.

•How do the metals/ alloys compare with water? What

would happen if they were mixed with water?

Part C: Analysis

Question 1: Identify the Unknown

A: Aluminum

B: Copper

C: Iron

D: Brass

Make corrections to this question in

red. Use the densities of these

metals for calculating percent error.

Percent Error

Part C: Analysis

In order to complete question 1, use this formula. The experimental value is the AVERAGE density of water that was calculated.

For Water: The accepted value for the density of water is 1.0 g/ml. Thus, for this example:

|0.990- 1.0|/1.0 * 100 = % error

Part C: Analysis

In order to complete questions 3 – 5, use this formula. The experimental value is your calculated values.

For Metal A: The accepted value for the density of Aluminum is 2.7 g/ml. Thus, for this example:

|3.031- 2.7|/2.7 * 100 = % error

Introduction to Graphs

Scatter Plots Line Graphs

Graphingy = mx + b

The Graph

• Graph the data that was MEASURED. Graph every table as a separate line on the SAME graph.

• NOTE: look at all the data points to determine the length of the axes and make intervals in units of 5 or 10.

• How do the metals compare to each other? To water?

• What does the slope signify?

Slope = y2 – y1/x2-x1

• What does it mean if the slope is steep?

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What would go here to follow how slope is found using the density formula?

And the winner is.....

Which was the most accurate

method to measure volume of the

solids?

What is your evidence?

Questions and Answers (Q/A)