After placing a liquid into a small-diameter glass tube, you observe the formation of a convex (upwardly curved) meniscus. What conclusion is correct?
a. The liquid must have a very low surface tension.
b. Strong adhesive forces exist between the liquid and glass.
c. The liquid must have an extremely high viscosity.
d. Strong cohesive forces exist among the liquid molecules.
ANS: D
When the liquid is water, the meniscus is concave because the water molecules at the surface ad-here to the glass more strongly than they cohere to each other. In contrast, a mercury meniscus is convex. In this case, the cohesive forces pulling together the mercury atoms exceed the adhesive forces trying to attract the mercury to the glass.
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Indicate whether this statement is true or false.
Which of the following abbreviations means the medication is taken orally?
PV PO PR SC