question_answer 1)

Use the periodic table to answer the following questions: (a) Identify an element with five electrons in the outer subshell. (b) Identify the element that would tend to lose two electrons. (c) Identify the element that would tend to gain two electrons. (d) Identify the group having metal, non-metal, liquid as well as gas at room temperature.

Answer:

(a) Halogens have five electrons in outer subshell, i.e., outer configuration ns^'np5. Examples are\[F,\text{ }Cl,\text{ }Br,\text{ }I,\text{ }At\], etc. (b) Alkaline earth metals have the tendency to lose two electrons. Examples are: \[Mg,\text{ }Ca,\text{ }Sr,\text{ }Ba\]and Ra. (c) Chalcogens have the tendency to gain two electrons. Examples are: O, S and Se. (d) Group 17 (halogen group) consists of metal, non-metal, liquid as well as gas at room temperature. F (gas and non-metal), \[\text{Cl}\](gas and non-metal) Br (liquid and non-metal), \[I\](solid and metal) At (Solid and metal)