Homenaje al Dr. Tirso Rios

On September 3rd it will take place an act in honor to Dr Tirso Rios, recently deceased on June 18th, at “Instituto de Química” from UNAM (Universidad Nacional Autónoma de México).

King cakes

The origin of kings’ cake dates from the roman times, and it was not a religious tradition. The cake was served at Saturnalia celebrations (Slaves festivity) in December. It was a commemoration of the renewal of light and the end of the labor in the countryside. At that time the peasants and the slaves had the opportunity to rest and recover from the efforts realized during months. In order to celebrate it, they prepared round cakes, which included figs, dates and honey, and distributed them as a gift for the work well done.
In the III century a dry bean was introduced inside the cakes. It was a symbol of prosperity, and the one that found it would be named “king of kings” during a certain time previously established.
It was in the IV century when the Church converted the festivities in Christian celebrations.
It was in France where they started to celebrate “Le Roi de la Fave” (The king of the bean). Children were the protagonists, and the one that found the bean in the cake was treated with gifts and pampered by everyone on the 6th of January.
Actually in Spain it is a tradition to have kings’ cake (Roscón de Reyes) during the Magic Kings day on the 6th of January, where the Christmas festivities end. Nowadays you can find a bean and a plastic baby or a similar figure. The one that gets the bean has to pay the cake and the one that gets the baby will have good luck.
In South Louisiana it is a tradition to have king cake for Mardi Gras. From the day after Kings Day until Ash Wednesday you can find king cakes in the bakeries, some of them have their own special recipes. These king cakes are decorated with the traditional Mardi Gras colors: purple, green and gold. Inside every king cake a plastic baby is hidden. The tradition is that each person takes a piece of cake, and the one that finds the plastic baby inside is obligated to host the next king cake party and supply the king cake.
It is probable that the New Orleans king cake evolved from the customs of old South Louisiana’s immigrants. In the Picayune cookbook says that New Orleanians started serving king cake as part of the Spanish celebration of King’s Day. However other food historians believe that the New Orleans king cake was really an Italian or a French tradition.
Here you will find an easy recipe of a king cake from Stephanie Gallagher The Iron Chef Mom.
Next, you can also find a recipe of kings’ cake (Roscón de Reyes) that was broadcasted by RTVE as part of the program “La mañana” on December 29, 2011.
I hope you are able to make both cakes and compare them. Happy Mardi Gras!

Roscón de reyes

Happy Valentine's day

As a Valentine’s day gift I propose you to watch a video from the University of Leicester Department of Chemistry where you can see three experiments somehow related to love. The first one is called “Love chemistry” and emulates a heart where a colorless compound [(NH₄)SCN] is added to a yellow compound (FeCl₃) to yield two products with a blood red color. The second one is called “The thunder storm” where ethanol, sulphuric acid and potassium permanganate are mixed together in a beaker to react like a storm with some lightning. The third one is called “Mercury beating heart” in which a few drops of mercury are placed in a watch glass and some sodium thiosulphate and potassium dichromate are added around the mercury. When an iron nail touches the mercury, it looks like a heart beating. It is pure electrochemistry! I hope you will enjoy them.

Daniel Radcliffe sings "The elements"

Tom Lehrer was born April 9, 1928. He earned a Bachelor (1946) and a Master (1947) in Mathematics at Harvard. He remained at Harvard as a graduate student until 1953. During this time, he wrote "The Physics Revue", a collection of academic song parodies and among them is "The elements".

In a TV Show "The Graham Norton Show" at BBC, Harry Potter star Daniel Radcliffe performs "The elements". I hope you enjoy the sketch.

Stoichiometry rules

Here you have a song by Mark Rosengarten, that explains how to convert among grams, liters of ideal gas at STP and number of molecules via their common factor: moles. I hope it will help you to do the stoichiometry problems.

Emisiones de CO2

En el día de hoy finaliza la Cumbre del Clima de Cancún, en la que están representados 193 países. Esperemos que se pongan de acuerdo para limitar las emisiones de CO₂ para disminuir la subida de la temperatura. Y más importante, que lo lleven a cabo. Debido al exceso de emisiones de dióxido de carbono y otros gases contaminantes se está calentando la atmósfera. A continuación tienes un juego "Alerta CO₂". Este juego ha sido realizado por Acciónatura y ha sido subvencionado por el Ministerio de Medio Ambiente. Si después de ver la animación que hay al principio, decides jugar, deberás reducir las emisiones de CO₂ de la ciudad de Metrópolis.

¡Atrévete y redúcelas!

El día del mol es una fiesta no oficial celebrada por los químicos el día 23 de octubre entre las 6,02 AM y las 6,02 PM. La hora y el día derivan del número de Avogadro que es aproximadamente 6,02 x 10²³ definiendo el número de partículas (átomos o moléculas) en un mol de sustancia.
Existe una Fundación llamada NMDF (National Mole Day Foundation) que recopila las actividades desarrolladas a lo largo de los años, al mismo tiempo que sugiere actividades para desarrollar. Puedes visitar su página web haciendo clic en este enlace.

A continuación les invito a escuchar una canción relacionada con el día de hoy donde se celebra el día del mol.

¡Feliz día del mol!

Happy mole day to you!