Players read questions about energy levels and score points by picking the correct element as the answer. Electrons are in regions around the nucleus ... After the second level has 8 electrons, the ...

For example, mercury is a liquid at room temperature. The metals in Group 1, such as lithium, sodium and potassium, are all soft. Many non-metals have low melting and boiling points. When non ...

A pure substance made from more than one type of element chemically bonded together. Elements bond in fixed ratios and so can be represented by a chemical formula. For example, sodium chloride has ...