Question

Why organic matter decrease the surface tension in the water?

Answer 1

Answer:

Water is cool, it suppresses heat, it puts out fires and sometimes there is much water to spare. However, the high surface tension of water can reduce its effectiveness in suppressing some fires. Surfactants are compounds that reduce the surface tension of water.

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Answer 2

$\huge \tt \red{Answer}$

Surface tension of water is decreased with organic matter because the chemical behavior of alcohols is almost entirely determined by the hydroxyl group, since the alkyl portion of the molecule is relatively unreactive. Hydrogen bonding is not as extensive in ethanol as in water, and so its boiling point is lower than water's, despite its greater molecular weight.