Final answer:
When using different masses of a substance, you can expect different results because the amount of matter changes. Mass, measured against a standard kilogram, remains constant regardless of location, affecting volume and density measurements. Different substances with the same mass, like gold and cotton balls, will have different volumes due to their varying densities.
Step-by-step explanation:
The student has altered the volume of water being used, which changes the concentration of the solution but not the number of moles of solute. Mass is a measure of the amount of matter in a substance, and when using different masses of a substance, we can expect different results because the amount of matter (atoms and molecules) varies. The mass determined in comparison to the standard mass of 1 kilogram does not change irrespective of the location because mass is independent of location, unlike weight, which is the gravitational force acting on a mass.
In a scientific context, different masses of a substance would result in different mass measurements when using a balance. Additionally, altering the mass of a substance would also affect its volume and density since density is defined as mass per unit volume.
To illustrate, consider two substances: gold and cotton balls. Both can have the same mass, but since their densities are very different, they will occupy different volumes. This understanding of mass, volume, and density is essential in various scientific fields, including chemistry.