density
Are You Dense?
Deborah McMurtrie, Ph.D. Bridget Coleman, Ph.D. Gary Senn, Ph.D. University of South Carolina Aiken Handouts for this session can be found on the AMLE2015 app Or
http://rpsec.usca.edu/Presentations/AMLE2015/
Density • DENSITY is a physical property of ma8er; how ;ghtly packed the molecules are • The symbol most oAen used for density is ρ (the lower case Greek le8er rho). • The formula to calculate density is ρ = m / V
ρ = m / V Density = Mass divided by Volume What does that mean, exactly?
What is Mass? • Mass is the amount of ma8er in an object. • Mass is how heavy something is (but without gravity). • We measure mass in grams (g) and kilograms (kg).
What is Volume? • Volume is how much space something takes up. • Volume is the amount of 3-‐dimensional space an object occupies. • We measure volume in milliliters (mL), liters (L), cubic cen;meters (cc), or cubic meters (m3).
Displacement To find the volume of an irregularly shaped mineral (Garnet): 1. 2. 3. 4. 5.
Fill the beaker with water up to the 10mL line. Carefully place the mineral in the water. Where is the water line now? Subtract 10mL from the new measurement. That number is the volume of your mineral. (Cubic cen;meters)
Density of Minerals • The minerals in your box all have the same VOLUME but each has a different MASS. • Feel each mineral sample. Es;mate the order from lightest to heaviest. Record your guess. • Measure the MASS of each mineral and record your results. Compare. • You will have 15 MINUTES for this ac;vity!
Estimate the Order
Bauxite
Galena
Quartz
Fluorite
Pyrite
Garnet
Feel each mineral sample. Estimate the order of the masses.
Measure the masses. Record on the lines.
B = Bauxite
=________ g
P = Pyrite
= ________g
F = Fluorite
=________ g
Q = Quartz
= ________g
G = Galena
=________ g
R = Garnet
= ________g
Write the masses in number order, from least to greatest.
Take 4 Measurements • You will have 10 MINUTES for this ac;vity. • Six substances: Water, sand, salt, wood, iron filings, and rubbing alcohol • You will take 4 measurements of one substance: 25mL, 50mL, 75mL, and 100mL. Record your results for each on your data sheet.
Density= Mass divided by Volume Measure and record the mass for each substance. Graph the results. Calculate to find density. SAND Average Density = _________
SALT Average Density = ___________
IRON FILINGS Average Density = ___________
Volume (mL) 25 mL
Volume (mL) 25 mL
Volume (mL) 25 mL
Mass (g)
Density (g/mL)
Mass (g)
Density (g/mL)
Mass (g)
Density (g/mL)
50 mL
50 mL
50 mL
75 mL
75 mL
75 mL
100 mL
100 mL
100 mL
WATER Average Density = ___________
WOOD Average Density = ___________
RUBBING ALCOHOL Average Density = ___________
Volume (mL) 25 mL
Volume (mL) 25 mL
Volume (mL) 25 mL
Mass (g)
Density (g/mL)
Mass (g)
Density (g/mL)
50 mL
50 mL
50 mL
75 mL
75 mL
75 mL
100 mL
100 mL
100 mL
Mass (g)
Density (g/mL)
Calcula;ng Density • Use your calculator to calculate the density of your substance. • Density = MASS divided by VOLUME (g/mL) • Record your answers.
Graphing Density • Your team will plot the data for ONE substance on a transparency. • X axis: Horizontal (bo8om) shows VOLUME • Y axis: Ver;cal (side) shows MASS • Connect the 4 data points by drawing a straight line. • When you have finished, please bring your transparency to the front.
Puhng It All Together • Density is the rela;onship between mass and volume. • Graphing the data points shows this rela;onship. • Water has a slope of 1. • Substances with a slope >1 will sink. • Substances with a slope
Deborah McMurtrie, Ph.D. Bridget Coleman, Ph.D. Gary Senn, Ph.D. University of South Carolina Aiken Handouts for this session can be found on the AMLE2015 app Or
http://rpsec.usca.edu/Presentations/AMLE2015/
Density • DENSITY is a physical property of ma8er; how ;ghtly packed the molecules are • The symbol most oAen used for density is ρ (the lower case Greek le8er rho). • The formula to calculate density is ρ = m / V
ρ = m / V Density = Mass divided by Volume What does that mean, exactly?
What is Mass? • Mass is the amount of ma8er in an object. • Mass is how heavy something is (but without gravity). • We measure mass in grams (g) and kilograms (kg).
What is Volume? • Volume is how much space something takes up. • Volume is the amount of 3-‐dimensional space an object occupies. • We measure volume in milliliters (mL), liters (L), cubic cen;meters (cc), or cubic meters (m3).
Displacement To find the volume of an irregularly shaped mineral (Garnet): 1. 2. 3. 4. 5.
Fill the beaker with water up to the 10mL line. Carefully place the mineral in the water. Where is the water line now? Subtract 10mL from the new measurement. That number is the volume of your mineral. (Cubic cen;meters)
Density of Minerals • The minerals in your box all have the same VOLUME but each has a different MASS. • Feel each mineral sample. Es;mate the order from lightest to heaviest. Record your guess. • Measure the MASS of each mineral and record your results. Compare. • You will have 15 MINUTES for this ac;vity!
Estimate the Order
Bauxite
Galena
Quartz
Fluorite
Pyrite
Garnet
Feel each mineral sample. Estimate the order of the masses.
Measure the masses. Record on the lines.
B = Bauxite
=________ g
P = Pyrite
= ________g
F = Fluorite
=________ g
Q = Quartz
= ________g
G = Galena
=________ g
R = Garnet
= ________g
Write the masses in number order, from least to greatest.
Take 4 Measurements • You will have 10 MINUTES for this ac;vity. • Six substances: Water, sand, salt, wood, iron filings, and rubbing alcohol • You will take 4 measurements of one substance: 25mL, 50mL, 75mL, and 100mL. Record your results for each on your data sheet.
Density= Mass divided by Volume Measure and record the mass for each substance. Graph the results. Calculate to find density. SAND Average Density = _________
SALT Average Density = ___________
IRON FILINGS Average Density = ___________
Volume (mL) 25 mL
Volume (mL) 25 mL
Volume (mL) 25 mL
Mass (g)
Density (g/mL)
Mass (g)
Density (g/mL)
Mass (g)
Density (g/mL)
50 mL
50 mL
50 mL
75 mL
75 mL
75 mL
100 mL
100 mL
100 mL
WATER Average Density = ___________
WOOD Average Density = ___________
RUBBING ALCOHOL Average Density = ___________
Volume (mL) 25 mL
Volume (mL) 25 mL
Volume (mL) 25 mL
Mass (g)
Density (g/mL)
Mass (g)
Density (g/mL)
50 mL
50 mL
50 mL
75 mL
75 mL
75 mL
100 mL
100 mL
100 mL
Mass (g)
Density (g/mL)
Calcula;ng Density • Use your calculator to calculate the density of your substance. • Density = MASS divided by VOLUME (g/mL) • Record your answers.
Graphing Density • Your team will plot the data for ONE substance on a transparency. • X axis: Horizontal (bo8om) shows VOLUME • Y axis: Ver;cal (side) shows MASS • Connect the 4 data points by drawing a straight line. • When you have finished, please bring your transparency to the front.
Puhng It All Together • Density is the rela;onship between mass and volume. • Graphing the data points shows this rela;onship. • Water has a slope of 1. • Substances with a slope >1 will sink. • Substances with a slope
