How can you tell the difference between a dense vs. sponge rubber compound from a sample?
150992
Weight.  Sponge rubber has a number of cells in it that are gas-filled, hence the name "sponge".  A piece of solid rubber will weight much more than a piece of sponge rubber.\n\nOf course, different rubbers also have slightly different densities, i.e. natural latex rubber will be different from silicone rubber, SIBS rubber, etc.
1062254
Lol\nI actually did a test like this for my nephews science project last year.  Unless the formulas have changed the differences are completly negligent.  Their lasting time is about the same.
904937
ref\n\nhttp://www.cem.msu.edu/~reusch/VirtualText/polymers.htm
464277
A two part epoxy filler.
792670
Carpet is formed from nylon and polypropylene.  The polypropylene depending on its isomeric state (isotactic, syntactic, etc.) and its chain length will have different thermal properties, thus a low or high softening temperature.
1015799
Use the second derivative test, not sure exactly what it is still but it should be easy to find on the internet.
710153
Usually psi (pounds per square inch).\n\nAloha
968993
Color, shape, hardness, melting point, boiling point, density
306923
I'll go out on a limb and suppose that you need some very simple projects that can demonstrate polymer properties to the layperson.\n\nPhysics:  \n\nIf you take a rubber band, an elastomer, suspend a weight from it, and gently heat the rubber band with something like a hair drier, you can demonstrate that polymer chains prefer to adopt a random coil configuration rather than a straight, linear configuration. (I'll leave out the basic thermodynamic details so you can delve deeper into the subject.)\n\n\nChemistry:\n\nTo demonstrate the differences in size between polymers and small molecules, look up the size of a single water molecule and then get a piece of foam rubber.  The water molecule's size is on the order of Angstroms, while the foam rubber is essentially one gigantic molecule.\n\nIf you have access to sebacoyl chloride and hexamethylene diamine, you can make Nylon-6 by using equal parts of both reactants.  The polymer forms at the interface of the two liquids, and you can use tweezers to pull the polymer out of the reaction vessel.  NOTE:  Proper safety precautions MUST be followed as both chemicals are irritants. \n\nI've left out sources and a lot of other details so you can research the physics/chemistry of the examples given here.
1139007
If you asked a scientist you might get a different answer than if you asked a layman.  Let's compare a kilogram of lead with a kilogram of aluminum.  You likely would use the same scale to measure both samples.  But, the aluminum is much lighter and would take up far more space than the lead.  The samples would displace different amounts of air and the buoyancy of air would affect the scale readings by a small amount.  Therefore to obtain accurate measurements you must weigh the samples in a vacuum or calculate the buoyancy and compensate the weight measurements.  If this is true for lead and aluminum it is even more true for lead and feathers (or even lead and butter).  Chemists often do have to compensate for air buoyancy when measuring chemicals so that when they react none are left over.
1000766
The low technology approach is to use a densitometer.  This can be as simple as a hydrometer as used in the brewing industry to check for specific gravity (density).  From a measured density and a known volume and if you know the densities of both liquid components of a binary mixture you can work out the relative proportions of each using simultaneous equations and hence the concentration of one in the other.
542320
I would just recommend looking at a can and seeing what is the propellant.  We could guess all day, but as long as we don't work in a silly string factory we couldn't be absolute.  Alot of that kinf od informations i proprietary.  But how about this:\nPropellant\nSomething that dries fast (isopropyl)\nA plasticizer to keep the goo gooey\nsome other stuff
786996
This is a tricky question. Perhaps reading: http://www.newton.dep.anl.gov/askasci/chem03/chem03067.htm will help.
1161756
It's been a while since I took Chem, but if I remember correctly you can measure the mass of a non uniform rigid body using displacement. For example, if you have a beaker filled with water fill to the 50ml level and you insert a non uniform object into the beaker the the water level will rise. This change in the water level will equal the volume of the non uniform object. Then you can use the equation p=m/v and solve for the mass assuming that you know the p the density.
641835
What is the hoses material?\nAcrylonite butadiene styrene (ABS)?\nPlastic (General)?\nPolyethylene?\nPolyvinly chloride (PVC)?\n\nYou Should look to the Hazen-Williams Friction Loss Equation
367986
The two hardnesses you are looking for must be scratch and indentation hardness.\n\nScratch hardness is caracterized by the Mohs scale (as commented before).\n\nIndentation hardness is caracterized by serveral scales, the most popular (here, in colombia) are the Rockwell hardness test and the Shore durometer.\n\nThe wikipedia link has in itself references to detailded information about many hardness scales that you may find useful
593819
It appears that the constants are calculated at one condition (dry,wet,etc) whereas the effective is closer to reality.  See\n\nhttp://www.pnas.org/cgi/content/full/102/45/16293