The reactivity series: test metals in a virtual lab and build the order

Guide · Updated 2026-11-10

How displacement reactions reveal the reactivity series, why a metal's place decides how it reacts with acid and how it is extracted, and how to build the series from your own tests.

Open the Reactivity series lab Free, in your browser, nothing uploaded.

Why does an iron nail grow a reddish-brown coat in copper sulfate, while a copper wire in iron sulfate stays exactly as it was? The answer is the reactivity series, a ranking of metals from the most eager to react down to the least. The reactivity series lab lab lets you drop metal strips into salt solutions and dilute acid safely, see the equation and the changes you would notice, and build the ranking from your own results. Every equation in the lab is balanced, and you can practise more in the equation balancer. The formula writer helps with salt formulas such as Al₂(SO₄)₃, and the galvanic cell builder shows the same order turned into battery voltages.

What it is

A metal atom reacts by giving away its outer electrons and becoming a positive ion. Some metals let go of those electrons very easily; others hold on. Rank them by how easily they let go and you get the reactivity series. Potassium comes first, gold last, and hydrogen sits between lead and copper as a marker.

The key test is a displacement reaction. Put a strip of metal A into a solution of a salt of metal B. If A is higher in the series, A gives its electrons to the B ions. B comes out of solution as solid metal, and A goes into solution as ions:

A + (salt of B) → (salt of A) + B

If A is lower, nothing happens. The same idea works with acid: a metal above hydrogen pushes hydrogen out of a dilute acid as bubbles of gas, and a metal below hydrogen does not.

The position also explains how each metal is won from its ore:

• Top of the series (potassium to aluminium): the oxides are so stable that only electrolysis of the molten compound will do.
• Middle (zinc, iron, lead): heating the oxide with carbon, usually as coke, takes the oxygen away.
• Low (copper, mercury): heating the ore in air is enough.
• Bottom (silver, gold): they are often found free in the ground.

How to use it

1. Pick a metal in the Metal strip list and a liquid in the Solution list.
2. Press Drop it in and watch the beaker: a coat may form on the strip, bubbles may rise, or the colour of the liquid may change. Below it you get a one-line answer, the balanced equation and a list of what you would see.
3. Press Test this metal in every solution to run the chosen metal through all eight liquids at once.
4. Look at Your results. Each test gives a ✓ (displaced) or ✗ (no reaction) in the grid, and the series built from your tests appears underneath. Clear results empties the grid.
5. In The reactivity series, tap a metal to see its place, how it behaves with water and with dilute acid, and how it is extracted.
6. Answer the five Check yourself questions, and press New questions for another set.

A worked example

Suppose you test only three strips: magnesium, lead and silver, each in every solution.

Magnesium gives a ✓ in every solution except its own. With silver nitrate the lab shows:

Mg + 2AgNO₃ → Mg(NO₃)₂ + 2Ag

and a coat of silver crystals grows on the strip. Magnesium is above all seven of the others: aluminium, zinc, iron, lead, hydrogen, copper and silver.

Lead fails against the magnesium, aluminium, zinc and iron salts, but it wins against acid, copper and silver. In acid it fizzes only very slowly:

Pb + 2HCl → PbCl₂ + H₂

Silver displaces nothing at all.

Now read the series from these results. Magnesium is above 7 others. Aluminium, zinc and iron are each above 4 (lead, hydrogen, copper and silver), so they are tied. Lead is above 3. Hydrogen and copper are each above silver only, so they tie on 1. Silver is above 0.

The ties are the lesson. Three strips cannot separate aluminium, zinc and iron, because you never put any of them in a solution of another. Add a zinc strip and press the second button: zinc displaces iron and lead but not aluminium, and the tie breaks. Testing copper in acid then splits hydrogen from copper.

Where it is used

• Galvanising. Steel is coated with zinc. Zinc is above iron, so it corrodes first and protects the steel even where the coat is scratched.
• Sacrificial anodes. Blocks of magnesium or zinc are fixed to ship hulls and buried pipes for the same reason, and they are replaced as they wear away.
• Recovering metals. Scrap iron in copper-rich waste water from mines pulls the copper out as solid metal.
• Thermite welding. Aluminium takes oxygen from iron oxide so violently that molten iron forms.

Common mistakes

1. Reading the result backwards. If A does not displace B, then B is above A, not the other way round.
2. Testing potassium, sodium or calcium in solution. They react with the water itself before anything else happens. The lab flags them for exactly this reason, and real labs never use them for this test.
3. Judging aluminium by how it looks. A thin oxide film makes it slow to start, so it can seem less reactive than it is.
4. Calling hydrogen a metal. It is in the series only as a marker for the acid test.
5. Drawing a full series from too few tests. A tie means you have not compared those metals yet.

Questions people ask

Why does copper sulfate lose its blue colour? The blue comes from copper(II) ions. When a higher metal takes their place, the copper leaves the solution as metal, so the colour fades. Iron(II) ions left behind tint it pale green.

Is the reactivity series the same as the electrochemical series? They follow almost the same order. The electrochemical series puts a measured voltage on each metal, which is what the galvanic cell tool uses.