Question

which of the following observations best demonstrates waters special property of cohesion?
a. a spoon held near a stream of water from a tap deflects the water towards itself.

b. a rainbow forms after a rain storm.

c. water forms droplets of dew on a spider web in the morning.

d. water can dissolve other substances, such as sugar and salt.

Explanation:

• Option A: This is due to electrostatic attraction (the spoon may be charged) rather than cohesion. Cohesion is about water - water molecule attraction.
• Option B: A rainbow forms due to refraction, reflection, and dispersion of light in water droplets. It has nothing to do with the cohesive property of water.
• Option C: Cohesion is the attraction between water molecules. Water forming droplets (where water molecules stick to each other) on a spider web is a result of cohesion.
• Option D: This demonstrates water's property as a universal solvent (due to its polar nature), not cohesion.

Answer:

C. Water forms droplets of dew on a spider web in the morning.