A laboratory technician measures the mass of several weighed portions of a pure elemental solid and records the number of moles present in each portion. A graph of mass (vertical axis, grams) versus amount (horizontal axis, moles) is described as a straight line that passes through the origin.
Answer the following questions about this graphical relationship.
(a) Identify the physical significance of the point (0, 0) on the mass-versus-amount graph for a pure substance.
(b) Explain, in terms of the particle–mass connection, why the plotted data for a pure substance are expected to fall on a straight line rather than a curve.
(c) State the units associated with the slope of the line and describe the chemical quantity that the slope represents.