Based on the data, was zack, who ate the tofu, guilty of leaving a mess in the classroom?

Zack could not have made the mess because he ate Tofu which contains proteins.

Zack brought Tofu to the classroom and it contains protein.

The unknown food sample was tested for protein by:

The unknown food sample did not turn pink/purple so it did not contain proteins which is what Zack had in his tofu.

In conclusion, Zack could not have made the mess because the test did not indicate the presence of protein in the mess.

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The stronger the cohesive force, the stronger the surface tension. The water molecule has two hydrogen atoms bond to an oxygen atom through covalent bonding. ... Formed bonds are called hydrogen bonds which lead to strong cohesive forces between the water molecules and high surface tension of water.

The surface tension of water provides the necessary wall tension for the formation of bubbles with water. The tendency to minimize that wall tension pulls the bubbles into spherical shapes. Surface tension and droplets: Surface tension is responsible for the shape of liquid droplets.