Relative Atomic Mass: Complete Workbook & Interactive Simulation (AQA 4.1.1.6)

This is a complete workbook pack for Topic 4.1.1.6. It breaks down the calculation of Relative Atomic Mass (Ar) using a printable student booklet and an interactive simulation that visualises the “weighted average” concept.

What is in the Student Workbook (9 Pages):

Page 2: Definitions. Explains Ar compared to Carbon-12 and how to read it on the Periodic Table.

Page 3: Step-by-Step Guide. A clear, worked example using Chlorine (75% Cl-35 / 25% Cl-37) to demonstrate the formula: (mass×abundance)÷100.

Page 4: Guided Practice. Scaffolded calculation grids for Copper and Silver to build confidence.

Page 5-6: Independent Practice. Questions on Boron, Magnesium, and Silicon, plus standard exam definitions.

Page 7: Exam Practice. Standard questions (e.g., calculating Neon’s Ar to 2 decimal places) with tips on checking answers.

Page 8: Grade 9 Challenge. High-level algebra questions: “Calculate the percentage abundance of Lithium-6 given an Ar of 6.94”.

What is the “Ar Calculator” Simulation? I built this HTML tool to make the maths visual. It runs in any web browser.

Explore Mode: Students adjust abundance sliders for real elements (Cl, Cu, Mg, etc.). A visual “Balance Scale” tips to show how the weighted average shifts towards the more abundant isotope.

Live Calculation: Displays the step-by-step math (multiplication and addition) updating in real-time as sliders move.

Challenge Mode: A gamified quiz where students must adjust abundances to match a target Ar (e.g., “Match Chlorine’s 35.5”).

Reverse Challenge: A specific tool for the Grade 9 workbook questions, testing if students can work backwards from Ar to find abundance percentages.

Files Included:

Student Workbook (PDF) - 9 pages, ready to print.

Teacher Answers (PDF) - Full handwritten solutions and mark schemes.

Ar_Simulation.html - Interactive tool (works with and without internet).