Science.8.6.C

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The student is expected to describe the properties of cohesion, adhesion, and surface tension in water and relate to observable phenomena such as the formation of droplets, transport in plants, and insects walking on water;
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Knowledge and Skills Statement

Matter and energy. The student understands that matter can be classified according to its properties and matter is conserved in chemical changes that occur within closed systems.

Transport in Plants:
When plants evaporate water through their leaves, it is called transpiration. The movement of water within a plant causes negative pressure, a process known as the cohesion-tension mechanism.

the molecular attraction exerted between the surfaces of bodies in contact; creates a meniscus when measuring water in a plastic or glass graduated cylinder

a type of change in which a new substance is made from one or more previous substances; occurs during a chemical reaction; a change where the atoms of the original substances are rearranged to make new elements and/or compounds

a physical system that does not allow transfer of matter in or out, although energy can flow into and out of the system

the act or state of sticking together tightly; the attraction of water molecules to each other, creating the water droplet

substance that occupies space, has mass, and is composed of microscopic particles
 

detectable events that are observed through the senses or technology; can be explained through scientific laws, ideas, principles, and theories

characteristic of matter that can be used to identify particular materials

caused by cohesion, the attractive force exerted upon the surface molecules of a liquid by the molecules beneath that tends to draw the surface molecules into the bulk of the liquid and makes the liquid assume the shape having the least surface area

Research

Cavallo, Ann M. L., and Pamela A. Dunphey. “Sticking Together: A Learning Cycle Investigation about Water.” The Science Teacher 69, no. 8 (2002): 24–28. https://www.jstor.org/stable/i24155981

Summary: The properties of cohesion and surface tension of water are explored using water on two different surfaces in the article "Sticking Together: A Learning Cycle Investigation About Water." Students make observations about the surface tension of water when drops are added to a penny and when they touch the "dome" of water. Students then disrupt the tension with soap and make new observations.