IB MYP Integrated Science- Chemistry- Reactivity series of metals-Study Notes - New Syllabus

Reactivity Series of Metals

The reactivity series is a list of metals arranged in order of their reactivity, from most reactive to least reactive. It helps predict how metals will react and how they can be extracted from their ores.

The Reactivity Series

\( \mathrm{K,\ Na,\ Ca,\ Mg,\ Al,\ Zn,\ Fe,\ Cu,\ Ag,\ Au} \)

Metals at the top are highly reactive, while those at the bottom are less reactive.

Key Features of the Reactivity Series

• More reactive metals lose electrons more easily
• Less reactive metals are more stable
• Reactivity is linked to electron configuration

Reactions with Water

• Very reactive metals (K, Na, Ca) react vigorously with cold water
• Moderately reactive metals react with steam
• Less reactive metals do not react

Example:

\( \mathrm{2Na + 2H_2O \rightarrow 2NaOH + H_2} \)

Reactions with Acids

Metals above hydrogen react with acids to produce hydrogen gas.

\( \mathrm{Metal + Acid \rightarrow Salt + H_2} \)

Example:

\( \mathrm{Zn + 2HCl \rightarrow ZnCl_2 + H_2} \)

Displacement Reactions

A more reactive metal can displace a less reactive metal from its compound.

\( \mathrm{Zn + CuSO_4 \rightarrow ZnSO_4 + Cu} \)

Extraction and the Reactivity Series

• Top metals → extracted by electrolysis
• Middle metals → extracted using carbon
• Bottom metals → found native

Corrosion and Reactivity

More reactive metals corrode more easily.

• Iron rusts in presence of water and oxygen
• Less reactive metals like gold do not corrode

Link to Electron Loss

Reactivity depends on how easily a metal loses electrons:

\( \mathrm{Metal \rightarrow Metal^{+} + e^-} \)

Real-World Applications

• Predicting reactions in industry
• Preventing corrosion (galvanising)
• Designing extraction methods