A sealed discharge tube initially contains neutral magnesium vapor and chlorine gas
CHEMISTRY · Multi-part · AP · Chemistry · Atomic Structure and Properties · Atomic Structure and Properties
Problem
A sealed discharge tube initially contains neutral magnesium vapor and chlorine gas. Energetic electron collisions inside the tube create a mixture of the following species:
• neutral Mg atoms
• Mg⁺ ions
• Mg²⁺ ions
• neutral Cl atoms
• Cl⁻ ions
Assume the elementary charge magnitude is e=1.60×10−19C.
(a) For each of the five species listed, calculate the number of electrons present in a single particle. Use the periodic table values ZMg=12 and ZCl=17. Express each answer as an integer.
(b) A burst of ionization produces 1.00μmol of Mg2+ ions. Determine the total deficit of electrons (relative to the same number of neutral Mg atoms) created in this burst, and express the result as a net charge in coulombs.
(c) In a subsequent stage the tube reaches a steady state that must be electrically neutral overall. If the sample now contains 2.00×1017Mg2+ ions and an unknown number of Cl− ions (with negligible numbers of other charged species), determine how many Cl− ions are required to restore net charge neutrality. Explain your reasoning clearly in words as well as with appropriate calculations.