Salt: Properties & Separation Methods

V3 Updates
● Grew from 7 to 9 lessons; old numbers shifted
● Two new chemical-formula lessons (1.6, 1.8)
● Density Lab (1.3) reframed and moved later
● Exit Tickets built in; 1.9 expanded (Cherry Cola Distillation, Dead Sea Lab Practical)

V3 Updates
● New lessons include:
1.6 — What is table salt made of and why?
1.8 — Why does a chemical formula matter?

Both focus on chemical formulas, which the old unit barely touched.

● Lesson numbers shifted- Old lesson numbers may no longer point to the same content.

Key conceptual changes

● Concentration/Density Lab (new 1.3): reframed so the lab drives the question — students measure density and use it as evidence that salt is present even when they can't see it. The activity has been simplified a bit from last year, and the lesson sits later in the sequence so students build up basic lab skills and math/graphing first.

● Evaporation (new 1.4): sharpened around three connected ideas — temperature, states of matter, and particle models.

● Chemical formulas (new 1.6 & 1.8): a new two-lesson arc — first NaCl's 1:1 ratio, then subscripts and non-1:1 ratios (H₂O vs H₂O₂).

● Exit Tickets are now built in: quick formative checks at key points (Density and Concentration, Representing Gas/Liquid/Solid, Chemical Formulas)

● Assessment (1.9) is expanded: now includes a distillation application (Cherry Cola Distillation) and a Lab Practical ("What is the concentration of the Dead Sea?") where students apply the density/concentration method to a real sample.

● New investigations & activities: a Desalination warm-up (1.5), and in the new chemical-formula lessons, hands-on investigations — Ice Melt (calcium chloride vs. sodium chloride) and Hydrogen Peroxide vs. Water (1.8). Modeling is also now an explicit, tracked sequence — Model 1 in 1.2 and Model 2 in 1.4 — rather than scattered steps across lessons.