• Question: name 3 of the most reactive metals to water

    Asked by arora to Lauren, Marisol, Michael, Sarah, Sophie on 16 Nov 2016.
    • Photo: Marisol Collins

      Marisol Collins answered on 16 Nov 2016:

      Hi there!

      I had to think back to my A-level chemistry lessons to answer this one!

      Many metals will react with water, some quickly, some slowly (like Iron, which rusts), but some of the most explosive reactions are seen when metals in a group called the Alkali Metals react with water. These metals are found in group 1 of the periodic table (on the far left hand side), and they get more reactive as you go down the list. In school, I remember the teacher safely showing us what happened when we let samples of Lithium, Sodium and Potassium react with water – lots of fizzing and even sparks! We had to store these chemicals in oil to keep them safely away from air and water the rest of the time.

      The REALLY reactive alkali metals, Rubidium, Caesium and Francium, were too explosive and dangerous to keep at school, but I did a bit of research on the internet, and when these mix with water you can get really violent explosions!

      Did you know that you can test a substance to see if it contains one of the alkali metals by putting a sample in a flame? It will produce a different colour if it contains an alkali metal, for example orange for Sodium, red for Potassium and local for Lithium!

      Thank you for an interesting question!

      Marisol 🙂

    • Photo: Lauren Burt

      Lauren Burt answered on 17 Nov 2016:

      Hey!

      I remember doing this at school too, but the most reactive metals were potassium, sodium, lithium and calcium which reacted very fast when placed in water, but sometimes the water had to be heated into steam to see a reaction!

      Lauren 😀

    • Photo: Michael Rivera

      Michael Rivera answered on 17 Nov 2016:

      Archaeologists often dig up copper, iron and gold objects, particular from graves and ancient tombs! So because soil is mostly quite damp, different metal objects will be in a better or worse condition (and look different) depending on what they’re made of.

      Sometimes swords that are thousands of years old are recovered in pretty good condition after being dug up from mud – this is probably because iron does not react too quickly with water, and requires oxygen to start rusting. In the ground – there’s obviously little oxygen penetrating through the ground to the sword!

      Michael 🙂

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