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Hepatocellular carcinoma (HCC) is the sixth most common cancer and the third most common cause of mortality worldwide.

High school students find reaction stoichiometry and the concept of the mole hard to comprehend. Teachers are well aware of the importance of teaching the mole concept and also the difficulty associated with it. In an attempt to improve the understanding of the mole concept with reduced difficulty, an atomic model kit that provides a hands-on learning experience has been developed and implemented in a class of 40 students. Each model atom consists of spherical neodymium magnets (acting as nucleons) of appropriate number (1 for hydrogen, 12 for carbon, 14 for nitrogen, and 16 for oxygen) enclosed in a hollow spherical Styrofoam casing (acting as an atom) that can be opened when required. These model atoms can be easily weighed using a laboratory balance, to obtain mass ratios of 1:12:14:16. This model kit provides an opportunity to have a hands-on learning experience of abstract concepts such as mass conservation in a balanced chemical reaction, excess and limiting reagents, and the mole and its relation to gram atomic/molecular mass. Herein, we provide a detailed description of the design criteria and the construction of the model atoms. We also provide the activity sheets with the necessary instructions to carry out the hands-on activities and the assessment sheets used for evaluation.