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Atomic Number and Mass Number of Elements: Atoms are the building blocks of matter. They are responsible for the format of all living and non-living things. Understanding their molecular structure and ...

The questions in this quiz are suitable for GCSE chemistry students studying early ideas about atoms, the structure of the atom, atomic number and mass number. If you struggled with the quiz, don't ...

The terms theory and model are defined, and students learn how a theory remains valid. Atomic Theory: The Development of the Atomic Theory: The terms theory and model are defined, and students learn ...

If you've learned all the elements from actinium to zirconium, it's time to head back to the periodic table, where there's a new, extremely heavy element in town. In case you forgot your high school ...

At the far end of the periodic table is a realm where nothing is quite as it should be. The elements here, starting at atomic number 104 (rutherfordium), have never been found in nature. In fact, they ...

Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. Cadmium, are you looking a bit chubbier these days? Improved ...