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.
On this day (9th January) in 1868, Danish chemist Søren Sørensen was born. He’s best known for developing the pH scale, which we’ve likely all encountered, to measure the acidity or alkalinity of solutions. This graphic gives a brief overview of the pH scale and what it means.
What do the various different arrows used by chemists all mean? That’s the question this short summary graphic aims to answer, by highlighting the most common arrows encountered in chemistry lessons and textbooks and giving a brief explanation of their use with examples.
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.
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!
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.
