1 of 8

Density and�Graphical Analysis

Fifth Station�Barnett Newman, 1962

2 of 8

What is meant by density?

  • How closely the particles of a substance are packed. (mass per unit volume)
  • This closeness depends on the strength of the intermolecular forces between the particles.

Solid

strong IMFs

high density

Liquid

fairly strong IMFs

fairly high density

Gas

very weak IMFs

very low density

3 of 8

Density Calculations

  •  

4 of 8

Density Calculations

  •  

5 of 8

Density Calculations

  •  

6 of 8

Density by Graphical Analysis

Look at the following graph.

What units are on the y-axis?

What units are on the x-axis?

What is the equation for slope?

What units would the slope have for this graph?

Recognize those units?

7 of 8

Density by Graphical Analysis

When mass and volume data are collected for samples of a substance and graphed as M vs. V, the slope of the line is the density of the substance.

This technique is called graphical analysis.

8 of 8

Lab Time!

You are going to perform a lab to determine the average density of a sample of pennies.

You will graph your data and determine the average density using a spreadsheet and graphical analysis.

You will determine how well your data fits the trendline using the correlation coefficient, R2.