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Metals and non-metals is a long chapter, and many students revise it as a pile of separate facts: which metal reacts with water, which oxide is amphoteric, what roasting means. The facts are easier to hold, and to use in an exam, when you hang them on one idea: the reactivity series. This post shows how that one list answers most questions in the chapter, works through ionic bonding step by step, and ends with a practice routine.
What does the CBSE syllabus ask for in this chapter?
The CBSE Class X Science syllabus for 2026-27 lists, under Unit I: "Properties of metals and non-metals; Reactivity series; Formation and properties of ionic compounds; Basic metallurgical processes; Corrosion and its prevention." Unit I, Chemical Substances, carries 25 of the 80 theory marks. Practical 3 in the same document asks you to put zinc, iron, copper and aluminium into each other's salt solutions and arrange them by reactivity. All examples below come from Chapter 3 of the NCERT Class 10 Science textbook. Check the syllabus for your own exam year before you revise.
How does the reactivity series help you answer questions?
NCERT's Table 3.2 lists, from most to least reactive: K, Na, Ca, Mg, Al, Zn, Fe, Pb, [H], Cu, Hg, Ag, Au. Learn it as a sentence you can recite, then use it three ways.
Reaction with water. Potassium and sodium react violently with cold water, calcium less so, magnesium only with hot water. Aluminium, iron and zinc react only with steam. Lead, copper, silver and gold do not react with water at all.
Displacement. A metal higher in the series displaces a lower one from its salt solution. Iron in copper sulphate solution: Fe + CuSO₄ → FeSO₄ + Cu, so the nail gets a brown coat of copper. Copper in iron sulphate: no reaction, because copper is lower.
Extraction. NCERT's Figure 3.9 splits the list into three bands. K to Al are obtained by electrolysis of their molten compounds. Zn, Fe and Pb are reduced from their oxides using carbon. Metals near the bottom, such as gold and silver, are often found free in nature.
A worked example. The thermit reaction joins railway tracks: Fe₂O₃ + 2Al → 2Fe + Al₂O₃ + heat. Why does it happen? Aluminium is above iron, so it can take oxygen from iron oxide. Check the balance: 2 Fe on each side, 3 O on each side, 2 Al on each side. Aluminium is oxidised (it gains oxygen) and iron oxide is reduced. So much heat is released that the iron comes out molten.
How do you show the formation of an ionic bond?
An ionic compound forms when a metal atom gives electrons to a non-metal atom, so both reach a full outer shell. Here is magnesium chloride, which NCERT draws in Figure 3.6.
Write electronic configurations. Mg is 2, 8, 2. Cl is 2, 8, 7.
Decide who loses and who gains. Magnesium loses its 2 outer electrons to become Mg²⁺ (2, 8). Each chlorine needs 1 electron to become Cl⁻ (2, 8, 8).
Balance the electrons. Two electrons lost need two chlorine atoms to take them, which is why the formula is MgCl₂ and not MgCl.
Draw it. Show the two outer electrons of Mg as crosses, an arrow from each to a different Cl, then the ions in brackets with their charges.
Then link structure to properties, which is how board questions are usually framed. Ionic compounds have high melting points because a lot of energy is needed to break the strong attraction between ions; NCERT's Table 3.4 gives 1074 K for sodium chloride. They conduct electricity when molten or dissolved in water, because the ions can then move, but not as solids, where the ions are held in place.
Which mistakes cost the most marks?
Saying sodium chloride is made of molecules. NCERT notes it exists as an arrangement of oppositely charged ions, not as NaCl molecules.
Saying ionic solids conduct. They conduct only when molten or in solution.
Mixing up roasting and calcination. Roasting heats a sulphide ore strongly in excess air (2ZnS + 3O₂ → 2ZnO + 2SO₂). Calcination heats a carbonate ore in limited air (ZnCO₃ → ZnO + CO₂).
Expecting hydrogen from nitric acid. Nitric acid is a strong oxidising agent and oxidises the hydrogen to water. NCERT gives magnesium and manganese with very dilute nitric acid as the exceptions.
Forgetting amphoteric oxides. Aluminium oxide and zinc oxide react with both acids and bases to give salt and water.
A practice routine for this chapter
Recalling facts from memory builds longer-lasting memory than reading them again. In Roediger and Karpicke (2006), students who took recall tests on a passage remembered more of it days later than students who reread it, even though rereading made students feel more confident. Use that in four short sessions.
Day 1. Write the reactivity series from memory, then add one fact beside each metal: how it reacts with water, how it is extracted.
Day 2. Predict ten displacement reactions (for example, zinc in copper sulphate, copper in silver nitrate, lead in zinc sulphate). Write "reacts" or "no reaction", and the equation where it reacts.
Day 3. Draw electron transfer diagrams for NaCl, MgCl₂, Na₂O and MgO without the book, then check against NCERT.
Day 4. Answer the chapter-end questions on alloys and corrosion aloud, as if explaining to a friend. Our revision plan for Class 10 science shows how to fit this into a full term.
If a single idea will not stick, such as why aluminium needs electrolysis while zinc does not, look it up on its own. The Fermi Concept Library covers every concept in chemistry with its own lesson, so you can revise "reactivity series" or "ionic bonding" in isolation before going back to mixed questions.
Tonight, write the reactivity series from memory and mark the three extraction bands next to it.
