Science · Honors Chemistry
Chapter 1: Quantitative Foundations
Concentration times volume is a number of moles.
Ben mixes 30.0 mL of 0.100 M potassium iodide with 20.0 mL of 0.100 M lead(II) nitrate, and yellow lead iodide settles out. A drop more iodide in the clear liquid above makes more yellow solid.
Ben supplied more iodide than lead nitrate. How can the iodide be the reactant that ran out?
Make your guess to turn the page.
Still to come: 10 pages · Lab · Words to Know · What We Learned · 4 questions · Explain It in Writing · Open Questions
The idea this lesson is working on — Students pick the reactant present in the smaller amount as the limiting one. The book opens on Ben’s iodide, supplied in larger amount and still used up, then runs equal amounts of hydrogen and oxygen in the lab. Ask: how many times could the equation run on each reactant alone? The idea to reach is moles divided by coefficient.
Gay-Lussac’s assay — Gay-Lussac’s instruction for the wet assay of silver appeared in 1832, and he had introduced the words burette and pipette in 1824. The 100 mL to 1.000 g design is the standard account of his normal salt solution; the molarity is worked here from modern molar masses.