[rachel]

I have been assigned a final project in grade 12 chemistry class.  For this project, we are required to have a contact who is knowledgeable in the area we are researching.  If someone is able to answer a few questions about the surface tension of water and how solutes and other factors effect it, it would be greatly appreciated.
1. How can solutes cause an increase/decrease in the surface tension of water?
2. Does temperature have an effect?
3. What causes a meniscus to form?
4. What other factors can change the surface tension of water?

[Jiro]

I'm going to give this a shot. I'm just learning about chemistry so I might not be so knowledgeable but I'll try to do my best... Study intermocular forces because intermolecular forces gives rise to a number of structural features and properties of liquids.
1)Liquids that have strong intermolecular forces also have high surface tensions...
Surface tension:
Water(Hydrogen Bond) > any other(most) liquids
So i believe, the solute increases its polarity it will increase the tension and vice versa.
2)Not sure... but id guess it make the bonds less stable and thus weaker intermolecular forces.
3)Menisucus: molecules in liquids are pulled in all directions by intermolecular forces. Moluecules at the surface are only pulled down and sideways by other molecules and not upwards. Polar and non-polar repel. So i think the glass surface is polar.
4)Any other way you can change the intermolecular forces(stronger or weaker). For water I think you can add flourine since strength of the hydrogen bonds are determined by the electrostatic attractions between the lone pair electrons of the electronegative atom and the hydrogen nucleus.