Question

read the passage and answer the next two questions. during a classroom experiment, a burning magnesium ribbon was dropped into a glass test tube filled with oxygen. a bright white flame was produced. a white powdery substance formed at the end of the reaction. which of the following statements about the element from which the ribbon was made, are true? select all that apply it has two valence electrons it has three valence electrons it belongs to the third group it belongs to the third period

Explanation:

Magnesium (\(Mg\)) has an atomic number of \(12\). Its electron configuration is \(1s^{2}2s^{2}2p^{6}3s^{2}\). The outermost shell (\(3s\)) has \(2\) electrons, so it has two valence electrons. In the periodic table, elements are arranged in periods (rows) and groups (columns). Magnesium is in the third period (row \(3\)) and the second group (column \(2\), alkaline - earth metals).

Answer:

It has two valence electrons; It belongs to the third period.