Because you were unable to get the needle to float on vegetable oil, does this mean that needles do not float?

Question

on vegetable oil? Explain?

Lab Results:

Surface Tension

Needle floats on distilled water
Needle does not float on acetone
Needle does not float on vegetable oil

Viscosity

Time for water to drain from bottle: 28 sec, 27 sec, 26 sec
Time for veg oil to drain from bottle: 1 m 15sec, 1m 16sec, 1m 15sec

Time for 5w-30 Motor oil to drain: 11m 55sec, 11m 54sec, 11m 53sec
Time for 20W-50 motor oil to drain: 35 m, 34 m 98sec, 34m 99 sec

Answer 1

I've answered your chemistry/science questions before, smartie. Feel free to write me at [e-mail]
for help with science questions.

Anyway.....it's not really buoyant in water in the same sense floating objects are. If you can see it on the surface it's sunk down in a good ways. It's not even wet. The cohesion of water to water is strong and the adhesion of water to steel is relatively weak. So surface tension holds the water together and repels the steel, so it's buoyed up.
Acetone and vegetable oil lack the cohesion to have a surface tension that holds up the needle.
The viscosities will not matter in this argument.

Answer 2

You're looking for density for floating. The needle doesn't really float on the distilled water. It's held above by the surface tension of the water. Viscosity is irrelevant.

Try a denser liquid, like mercury.

Answer 3

Hi. The needle does not float, even on water. It is held up by surface tension because water has more attraction to itself than to the needle. Vegetable oil, acetone, alcohol, even engine oil do not have the same attractive strength.

Answer 4

The needle didn't actually float on the water. Water has a small tension membrane on it's surface.

Answer 5

witches made of wood float as do ducks