If an atom or ion has an atomic number of 3, 2 electrons, and the electronic configuration is 2, what is the mass number? ​

Identify one disadvantage to each of the following models of electron configuration: -dot structures -arrow and line diagrams -written electron configurations type in your answer below. (answer) -dot structures do not show the distribution of electrons in orbitals and take up a lot of space. -arrow and line diagrams take up a lot of space and make it difficult to count electrons. -written configurations make it easy to lose count of electrons and do not show the distribution of electrons in orbitals.

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Which element is the least metallic between cadmium, silver, zinc, or iron?