Question

The elements in groups 1a, 6a, and 7a are called ______, respectively?

1) Alkali metals, Halogens, Noble gases
2) Alkaline earth metals, Transition metals, Metalloids
3) Lanthanides, Actinides, Rare earth metals
4) Nonmetals, Metalloids, Transition metals

Answer 1

The elements in groups 1a, 6a, and 7a are correctly termed alkali metals, chalcogens, and halogens, respectively. None of the provided options in the question contain this exact sequence, as noble gases are actually in group 8a, not 7a.

Step-by-step explanation:

The elements in groups 1a, 6a, and 7a are called alkali metals, chalcogens, and halogens, respectively. The first column of the periodic table, group 1, contains the alkali metals which are highly reactive and form compounds with one atom of hydrogen. Group 6, the chalcogens, include elements like oxygen and sulfur, while group 7, the halogens, are reactive nonmetals. The noble gases actually belong to group 8a and are known for their lack of reactivity.

Choosing from the options provided in your question, the most appropriate answer would be: 1) Alkali metals, Chalcogens (not listed in the options), Halogens. Therefore, none of the options you've provided are completely correct, since noble gases, which were mentioned in the first option, belong to group 8a. An answer choice with the correct sequential order would look something like this: Alkali metals, Chalcogens, Halogens.