1. Nitrogen Triiodide is an extremely sensitive explosive compound that, when dry, can be detonated by the lightest of touches or vibrations. For this reason, it should never be contained or transported and we are not aware of any industrial uses.

    A quantity of NI3 was prepared in the Ri Prep Room before being laid out to dry in the famous Lecture Theatre. This process took over two hours and, due to the extreme shock-sensitivity of the material, we were only able to attempt the reaction on this scale once. The crew were forced to wear ear defenders at all times in case the material spontaneously exploded.

    As Dr Peter Wothers initiates the reaction, the Nitrogen Triiodide detonates incredibly quickly in a fraction of a second to release a purple cloud of iodine vapour into the room.

    Peter Wothers explains further:

    "To tie in with the theme of the first Christmas Lecture (Air), I wanted to show the rapid production of a gas, but unfortunately almost all gases are colourless. The rapid production of iodine vapour from NI3 seemed like the perfect solution. The most amazing thing for me was the delay visible from the slow-mo footage before the force of the explosion really hit me in the chest!"

    Devised to promote the 2012 Christmas Lectures, this is one of three large-scale, chemistry demos that were too big (or too dangerous!) to perform in the Ri Lecture Theatre in front of 400 young people.

    This experiment was undertaken under the supervision of professionals and should not be replicated.

    More about the 2012 Christmas Lectures: richannel.org/christmas-lectures/2012/peter-wothers

    # vimeo.com/56009513 Uploaded 6,823 Plays 0 Comments
  2. Most people know the advice about never putting water on an oil fire. We joined Dr Peter Wothers on the roof of the Ri building in London to show exactly why.

    Above the famous Lecture Theatre, the team set up a clear protective shield around a beaker filled with 150ml of oil. This was heated over a Bunsen until a small fire was burning. Wearing a fire protective suit, Dr Wothers then poured water from a small cup directly onto the fire.

    The reaction is so violent because water and oil don’t mix. When the water is poured into the beaker of burning oil it sinks to the bottom and, due to the intense heat, vaporizes into steam almost instantaneously. With this phase change from a liquid to a gaseous state the water expands by up to 1700 times and forces the fire above it upwards. This oxygenates the oil and creates the huge flame you can see in the video.

    Peter Wothers explains more:

    "This is a great reaction to illustrate the topic of our second Christmas Lecture (Water), but it would also have done for Fire too if we had been presenting a fourth lecture. It is one of my favourite demos since it really rams home how dangerous it is to add water to an oil fire. I was never really aware of how large the flames are around me since I was busy concentrating on what I was doing!"

    Devised to promote the 2012 Christmas Lectures, this is one of three large-scale, chemistry demos that were too big (or too dangerous!) to perform in the Ri Lecture Theatre in front of 400 young people.

    This experiment was undertaken under the supervision of professionals and should not be replicated.

    More about the 2012 Christmas Lectures: richannel.org/christmas-lectures/2012/peter-wothers

    # vimeo.com/56009515 Uploaded 475 Plays 0 Comments
  3. This two minute video explains what isotopes are, using Carbon-12, Carbon-13 and Carbon-14 as examples.

    # vimeo.com/78079045 Uploaded 1,367 Plays 0 Comments
  4. This two minute video explains basic atomic structure, and outlines the roles of protons, neutrons, and electrons.

    # vimeo.com/78079680 Uploaded 2,756 Plays 0 Comments
  5. # vimeo.com/114654392 Uploaded 67 Plays 0 Comments

Quimica

andrea

Browse This Channel

Shout Box

Heads up: the shoutbox will be retiring soon. It’s tired of working, and can’t wait to relax. You can still send a message to the channel owner, though!

Channels are a simple, beautiful way to showcase and watch videos. Browse more Channels.