What is the purpose of adding isopropyl alcohol to the meter?

The purpose of adding isopropyl alcohol to the meter primarily relates to its ability to dispel foam on the surface of liquids. When conducting measurements, especially in solutions or samples that may produce bubbles or froth, the presence of foam can interfere with the accuracy and reliability of the readings. Isopropyl alcohol serves as a defoaming agent, effectively breaking the surface tension and allowing for a clearer measurement without obstructions.

While other options suggest possible intentions for using isopropyl alcohol, they do not accurately reflect its role in this context. Improving measurement accuracy is not directly achieved through the addition of isopropyl alcohol; rather, it is the removal of foam that helps ensure that measurements are taken from the liquid surface as intended. Additionally, decreasing the weight of the liquid or enhancing its color are not relevant to the function of isopropyl alcohol in this scenario. Thus, its primary utility lies in facilitating unobstructed observation and measurement by eliminating surface foam.