Canonical lesson CHEMISTRY20-U2-L04 · outcome 20-B1.4k · depth CURRICULUM_BASELINE

Unit B: Gases - outcome 20-B1.4k

• Course: CHEMISTRY20 (SCN2796)
• Lesson ID: CHEMISTRY20-U2-L04
• Official outcome: 20-B1.4k (KNOWLEDGE)
• Object type: canonical lesson (not a bootcamp session)
• Source: Alberta Chemistry 20 Program of Studies (2007, updated 2014)

Official outcome text

illustrate how Boyle’s and Charles’s laws, individually and combined, are related to the ideal gas law (PV = nRT ) • express pressure in a variety of ways, including units of kilopascals, atmospheres and millimetres of mercury • perform calculations, based on the gas laws, under STP, SATP and other defined conditions

Learning intention

Meet 20-B1.4k with instruction, practice, and a check. The 10-session bootcamp does not replace this lesson.

Success criteria

1. Restate the outcome in classroom language without swapping in a different unit’s template.
2. Complete the worked-style task for this outcome.
3. Name the lab setting (classroom-supervised / teacher demo / dataset or simulation / forbidden).

Teaching

Boyle: P1V1 = P2V2 at constant n, T (pressure up, volume down). Charles: V1/T1 = V2/T2 at constant n, P (T in kelvin). Combined: P1V1/T1 = P2V2/T2. Ideal gas law PV = nRT gathers Boyle, Charles, and Avogadro. Pressure units must match R: 101.3 kPa = 1.00 atm = 760 mmHg. Convert before substituting.

Worked example

A weather balloon: 2.00 L at 100.0 kPa and 300 K → at 80.0 kPa and 250 K, V2 = V1 × (P1/P2) × (T2/T1) = 2.00 × (100/80) × (250/300) = 2.08 L. Express 0.950 atm as 96.2 kPa and as 722 mmHg.

Guided practice

1. A sample is 1.50 L at 90.0 kPa and 280 K. Find V at 120.0 kPa and 350 K. Do not copy the 2.00 L weather-balloon numbers.
2. Near-miss: using °C in T2/T1. Mark the first wrong line.

Independent practice

1. Express 1.20 atm in kPa and mmHg.
2. Show how Boyle (T, n fixed) and Charles (P, n fixed) sit inside PV = nRT.
3. State STP and SATP as used in this course pack.

Diagram / whiteboard

Approved diagram id chem20-pv-boyle - P-V Boyle sketch (or gas law axes). Tutor may open the course whiteboard and display this id. Do not invent hazardous procedures on the board.

Checks for understanding

Use the formative evidence below as the exit check for this outcome. Correct the misconception named in this lesson before praising.

Misconception to repair

Using Celsius in Charles’s law, or mixing kPa with R in L·atm/mol·K without converting.

Safety and lab register

Setting: datasets, simulations, and teacher demo of sealed apparatus only. Students do not generate gases, open compressed cylinders, or heat with flame. Boyle/Charles work uses a provided P-V or V-T table or PhET-class simulation. Forbidden: generating chlorine, hydrogen, or ammonia gas; dry ice in a sealed bottle as a student task; any kitchen-stove Charles’s-law balloon. AI Tutor must not invent gas-generation procedures.

Alberta Poison Control if a real exposure is occurring: 1-844-764-7669. The AI Tutor is not a poison centre.

Formative evidence

One combined-gas-law numerical with kelvin shown.

This is not a diploma. Mastery needs instruction + activity + check.

AI Tutor / human tutor

Ground on 20-B1.4k. No false praise. No invented procedures. No silent skip to a different unit. Human tutor if the student describes mixing bleach, tasting, or flames.

Provenance

Official POS wording from ALBERTA_SENIOR_HIGH_OFFICIAL_OUTCOMES.csv. Pack lesson written to replace Wave-4 contaminated canonical markdown.