33. To accurately measure the density of a series of small irregular solids made of plastic, wood, fiberglass, and glass, which of the following laboratory tools will a student need?
Answer: A
Graduated cylinder, water, weighing balance are needed to measure the density of the irregular solids.
To measure the density of irregular solids, a student requires a graduated cylinder for measuring the volume of water displaced by the solid, a balance for measuring the mass of the solid, and water to facilitate the displacement method.
A) Graduated cylinder, water, weighing balance
This option is correct as it includes all necessary tools for measuring density. The graduated cylinder is used to measure the volume of water displaced when the solid is submerged, the weighing balance is essential for determining the mass of the solid, and water serves as the medium for the displacement measurement.
B) Weighing balance, Bunsen burner, metric ruler
This option is incorrect because, while it includes a weighing balance, it lacks a graduated cylinder and water, both of which are essential for measuring the volume of the solid needed to calculate density. The Bunsen burner is not relevant for density measurements, and the metric ruler does not assist in measuring the volume of irregular solids.
C) Graduated cylinder, spectrophotometer, water
This option is incorrect as it includes a spectrophotometer, which is not necessary for measuring density. Although it has a graduated cylinder and water, the absence of a weighing balance means the mass of the solid cannot be measured, making density calculations impossible.
D) Graduated beaker, metric ruler, water
This option is incorrect as it substitutes a graduated beaker for a graduated cylinder. While a graduated beaker can measure volume, it is not as precise as a graduated cylinder. Furthermore, the metric ruler does not contribute to measuring the volume of irregular solids, and thus cannot provide the necessary data for density calculations.
Conclusion
The correct answer is option A because it includes all required tools: a graduated cylinder for measuring displaced water volume, a weighing balance for mass measurement, and water for the displacement method. In contrast, all other options either lack essential tools or include irrelevant equipment, preventing accurate density measurement of the irregular solids.