A technician prepares an aqueous stock solution that
CHEMISTRY · Multi-part · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties
Problem
A technician prepares an aqueous stock solution that, within a standard analysis box, contains the following particles:
• 6 Ca²⁺ ions and 12 Cl⁻ ions (from completely dissociated CaCl₂)
• 6 urea molecules (NH₂CONH₂)
An identical analysis box is drawn for Solution X (the stock) and Solution Y, which is created by diluting one part of the stock with one equal part of pure water (thus doubling the total volume of liquid).
Answer the following questions regarding Solutions X and Y.
(a) For Solution Y, state the expected number of Ca²⁺ ions, Cl⁻ ions, and urea molecules that would be found inside a single analysis box after thorough mixing. Explain your reasoning quantitatively.
(b) Compare the concentrations of the ionic solute (CaCl₂) in Solutions X and Y. Express your answer as a simple numerical ratio ([CaCl2]Y[CaCl2]X) and justify it using the particle counts.
(c) Describe how the relative electrical conductivity of Solution Y would differ from that of Solution X, and account for the difference in terms of total charge-carrying particles present per analysis box.