Chemistry Assignment
Particles, Attractive Forces, and Energy
In this activity, you will look at numerous pieces of heat-related data for elements and compounds. You will use the data to draw conclusions about the forces that hold these materials together.
- Room-temperature phase compared to boiling points.
Material Name / Material symbol or formula / Room Temp. Phase / Boiling Temp. (°C) / Material Name / Material symbol or formula / Room Temp. Phase / Boiling Temp. (°S)
Water / Paraffin
Oxygen / Ethanol
Table salt / Copper
Helium / Nitrogen
a)What trend or pattern do you notice when comparing the room temp.phase and boiling point?
b)What do you conclude about the strength of the attractive forces in gases compared to liquids compared to solids?
- Molar heat capacities compared to category of material.
Material Name / Material symbol or formula / Category of material / Molar Heat Capacity / Material Name / Material symbol or formula / Category of material / Molar Heat Capacity
Aluminum / Copper
Water / Acetone
Ethanol / Gold
Zinc / Octane
a)What trends or patterns do you notice when comparing the molar heat capacity and category of material?
b)What do you conclude about the relationship between the inner structure of materials and their molar heat capacities?
- Heats of chemical changes compared to physical changes
Process / Chem or Phys change? / Heat per mole associated with the process / Process / Chem or Phys change? / Heat per mole associated with the process
Melting of ice / Neutralization of HCl with NaOH
Boiling of water / Sublimation of dry ice (CO2)
Burning of paraffin / Neutralization of HCl with CaCO3
Burning of methane / Melting of Paraffin
a)What trends or patterns do you notice when comparing the heats per mole to the nature of the changes?
b)What do you conclude about the nature of a change that occurs and the heat that’s associated with that change?
- Heats of combustion compared to the chemical formulas of the fuels
Name of fuel / Chemical formula / Heat of combustion / Name of fuel / Chemical formula / Heat of combustion
Methane / Acetone
Methanol / Butane
Ethane / Hexane
Ethanol / Octane
Propane / Dedecane
Propanol / Paraffin
a)What trends or patterns do you notice in the relationship between the amount of oxygen in the fuel and the fuel’s heat of combustion?
b)What trends or patterns do you notice in the relationship between the number of carbons in the fuel and the heat of combustion?
c)What do you conclude about the composition of fuels and the heat that they release when burned?
Write a conclusion to this activity in which you summarize what these data sets imply about the forces that hold materials together.