A scientist studies an element that has seven electrons in its outer shell, is fairly toxic, is a gas at room temperature, and is highly reactive. To which group of the periodic table does this element belong? (1 point)

Question

1-alkali metals

18-noble gases

17-halogens

2-alkaline earth metals

Answer 1

The element you are describing belongs to group 17, known as the halogens. Halogens have seven electrons in their outer shell, are often reactive, can be toxic, and include elements that are gases at room temperature, such as chlorine and fluorine.