IB Middle Years Programme · Sciences MYP Year 1

Chemical Reactions and the Periodic Table

Cover illustration for Chemical Reactions and the Periodic Table (Sciences MYP Year 1).
MYP · Sciences MYP Year 1

Chemical Reactions and the Periodic Table

MYP Year 1 Sciences — Chemical Reactions and the Periodic Table

22 min readFoundationalCore Year 1 chemistry unit — assessed through Criterion A/C style tasks (data-based identify/describe/compare questions). MYP uses criterion-based assessment rather than a fixed exam percentage, but this content is the foundation every later MYP chemistry unit builds on.

Every metal in your pencil case, phone and school gate was chosen for a reason — density, conductivity and resistance to rust decide whether a lump of ore ends up as a drinks can or a power cable. This topic trains you to read a data table (melting point, density, cost) and argue why a material fits a job, then to classify what's actually happening when something burns, rusts or fizzes. The command word does the heavy lifting here: Identify wants a bare fact, Describe wants that fact plus the reason it matters — mixing the two up is where most marks go missing.

Overview

This unit has two jobs: sort elements/materials by their properties (metals vs non-metals, the periodic table's layout), then explain what happens when substances actually react — rusting, burning, fizzing, cooking. Nearly every exam question hands you real data (a table of densities, melting points, costs) and asks you to reason from it, not recite a definition from memory.

  • Metals and non-metals differ in a predictable set of physical properties — that predictability is what lets engineers pick materials.
  • The periodic table isn't just a wall poster — its layout (groups, periods, metal/metalloid/non-metal zones) tells you how an element will behave before you even test it.
  • Reactivity explains why some metals need painting and others self-protect — same chemistry (reaction with oxygen), very different outcome.
  • Chemical changes are identified by evidence (gas, colour, precipitate, heat) and by one hard test: can you get the original substance back by simple physical means?

The shape of the chapter

Command terms that decide your mark in this topic

Command termWhat it demandsAOMark-earning move
IdentifyState a fact or name, pulled from given information or recall — no explanation required.AO1 (Knowing & understanding)1 mark for the correct name/property alone; adding reasoning here earns nothing extra and wastes time.
DescribeGive a detailed account: state the property/fact AND the reason it matters for the situation asked.AO1/AO2Usually 2 marks — 1 for the property, 1 for the explanatory link ('...because...').
CompareState similarities and differences between two or more things, using the actual data given.AO2/AO3Must explicitly reference both items — describing only one loses roughly half the marks.
ExplainGive reasons supported by evidence, showing a cause-and-effect chain.AO2Needs a 'because' link; a bare statement of fact with no reasoning scores 0.
OutlineGive a brief summary of the main points only.AO1Rewarded for breadth — one short line per point is enough, don't over-explain.
DistinguishMake clear the point of difference between two related concepts.AO2Reward is for the specific difference, not two separate unconnected definitions.

Key point

In this topic, marks live in the word 'because'. Q1–Q8-style questions almost always pay a second mark for linking a property to why it suits the job — not for repeating the property in different words.

Overview