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The deeply knowledge of the periodic table is one of the most important keys to understand the basic principles of Chemistry. Memorizing the elements of the groups and periods is one of the most commonly used strategies to learn the position of each element in the periodic table; nevertheless it is a hard task for most students. The use of card games can represent a useful alternative to teach some chemical aspects. Here, we present ChemMend, a new Chemical card game which will allow chemistry students to obtain a good ability in the periodic table. This game attracts the attention of the students, and it allows them to review mentally the period and group while playing; being the learning a consequence of the game. The ChemMend game will introduce and explore the periodic table in the classroom. ConclusionsChemMend has been found to be a useful tool for teaching the periodic table in an entertaining way, as the game has been designed to attract the attention of the students. The game allows students to review mentally the period and group for each play during the game and therefore this may allow students to learn the periodic table by playing the game. Thus, the developed card game will introduce a new manner to teach the periodic table in the classroom. ASSOCIATED CONTENTSupporting Information. A file with card images for printing and a periodic table. This material is available free of charge via the Internet at http://pubs.acs.org

The combination of DNA and π-conjugated polyelectrolytes (CPEs) represents a promising approach to develop DNA hybridization biosensors, with potential applications for instance in the detection of DNA lesions and single-nucleotide polymorphisms. Here we exploit the remarkable optical properties of a cationic poly[3-(6'-(trimethylphosphonium)hexyl)thiophene-2,5-diyl] (CPT) to decipher the self-assembly of DNA and CPT. The ssDNA/CPT complexes have chiroptical signatures in the CPT absorption region that are strongly dependent on the DNA sequence, which we relate to differences in supramolecular interactions between the thiophene monomers and the various nucleobases. By studying DNA-DNA hybridization and melting processes on preformed ssDNA/CPT complexes, we observe sequence-dependent mechanisms that can yield DNA-condensed aggregates. Heating-cooling cycles show that non-equilibrium mixtures can form, noticeably depending on the working sequence of the hybridization experiment. These results are of high importance for the use of π-conjugated polyelectrolytes in DNA hybridization biosensors and in polyplexes.