General Chemistry

Infographic on litmus paper. The graphic explains how litmus dyes can be derived from orcinol, itself sourced from species of lichens. The chromophore of the litmus dye is 7-hydroxyphenoxazone. In acidic solutions, the protonated structure is red, while in alkaline solutions the deprotonated structure is blue.

What links litmus paper and lichens?

Infographic on litmus paper. The graphic explains how litmus dyes can be derived from orcinol, itself sourced from species of lichens. The chromophore of the litmus dye is 7-hydroxyphenoxazone. In acidic solutions, the protonated structure is red, while in alkaline solutions the deprotonated structure is blue.
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Along with universal indicator, litmus paper is one of the most commonly encountered pH indicators in school chemistry lessons. Unlike the range of colours produced by the former, litmus is pink-red in acidic solutions and blue in alkaline solutions. This graphic highlights its complex origins in lichens and the chemical changes that account for its colour change.

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Sant Jordi St George's Day Chemistry

Celebrating Sant Jordi (Saint George’s Day) Chemistry with ICIQ

Sant Jordi St George's Day Chemistry
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April 23 is Saint George’s Day, celebrated in particular by a number of countries and cities where Saint George is the patron saint. One of these is, of course, England, though here the celebrations tend to be quite muted and minimal, and certainly nothing in comparison to the merriment that heralds St Patrick’s Day. In Catalonia, however, it prompts a good deal more in the way of celebration, and I made this graphic for the Institute of Chemical Research of Catalonia to illustrate some of its facets.

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March for Science 2017 – What's Chemistry Ever Done For Us-

The March for Science – Ten things that chemistry has done for us

March for Science 2017 – What's Chemistry Ever Done For Us-
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Across the globe this weekend hundreds of thousands of people in over 500 cities will be marching for science. Though many of those marching may be scientists, it’s not just for those in the scientific community; it’s for anyone who wants to show their support for the funding and continued advancement of science, and the importance of political policies being based on scientific evidence. It’s also about appreciating the role that science plays in our lives – and as this graphic shows, chemistry alone touches your life in more ways than you might have realised!

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The History of the Atom – Theories and Models

An infographic history of the atom. Dalton identified that atoms of a particular element differ from those of other elements. Thomson discovered the electron and described the 'plum pudding' model of the atom: electrons scattered throughout a cloud of positive charge. Rutherford identified that the positive charge was concentrated in the nucleus of the atom. Bohr modified Rutherford's model by stating that electrons move in orbits of fixed sizes and energies. Schrödinger stated that electrons do not move in paths around the nucleus but in waves.
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All matter is made up of atoms. This is something we now take as a given and one of the things you learn right back at the beginning of high school or secondary school chemistry classes. Despite this, our ideas about what an atom is are surprisingly recent: as little as one hundred years ago, scientists were still debating what exactly an atom looked like. This graphic takes a look at the key models proposed for the atom, and how they changed over time.

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