# Chemicals to increase surface tension of water

I want to increase the surface tension of water by 1.2 - 2 times. How about adding one or more chemical substances to the water that can possibily increase its surface tension by the desired amount? But I don't know what chemical substances to add. Do you what chemical substances can I add?

The surface tension of water is $$\pu{72 dyne/cm}$$; it is sometimes compared to mercury, which has a surface tension of $$\pu{486 dyne/cm}$$. The higher surface tension of the mercury is because the atoms of mercury bond much more tightly.
It is claimed that most inorganic solutes increase the surface tension of water. Another source suggests that surface tension could be increased if you increase the polarity of water by adding a more polar substance. But there seems to be contradictory evidence both $$\ce{NaOH}$$ and $$\ce{Na2S2O3}$$ decrease the surface tension of water. And there is an article that shows $$\pu{8M} \ \ce{NaCl}$$ to have a surface tension of about $$\pu{85 dyne/cm}$$. So it would seem that if there is an effect, it is small.