4 mistakes learners make with the reactivity series, each one named and explained.
Reactivity is about how readily a metal loses electrons, not how valuable or familiar it is.
Copper is described as not being a metal.
Reactivity questions can make an unreactive metal seem like an exception to everything.
Question. Where copper sits in the reactivity series
A common answer. copper is not a metal
The answer. copper is a metal, low in the series
Why. Copper conducts, is malleable and sits in the transition block.
Position in the reactivity series says nothing about whether something is a metal.
Two metals from opposite ends of the series are said to sit in the same place.
Metals share so many properties that it is easy to assume they share this one too.
Question. Copper compared with potassium
A common answer. they are equally reactive
The answer. copper is far less reactive
Why. Potassium has to be stored under oil; copper can sit on a roof for a century.
The reactivity series exists because metals differ enormously on exactly this.
A familiar metal such as iron or copper is chosen as the most reactive.
The best known metals are the ones you meet every day, which are the least reactive ones.
Question. The most reactive of potassium, iron, copper and gold
A common answer. iron
The answer. potassium
Why. Potassium reacts violently with water; iron takes years to rust.
If you have seen it used for a bridge or a coin, it is near the bottom of the series.
Gold is chosen as the most reactive, or its use in jewellery is explained by it being expensive.
Precious sounds like special, and special sounds like it should react strongly.
Question. Why gold is used for jewellery
A common answer. because it is expensive
The answer. because it is so unreactive that it never tarnishes
Why. Gold is expensive partly because it is unreactive, so the causation runs the other way.
Ask what the metal does chemically. Price is a fact about people, not about the element.
WAJD spots these patterns in your child's answers and names the one behind their wrong answers, instead of just marking them wrong.