Answer:
Na has the most similar configuration.
Explanation:
Na electron configuration: 1s²2s²2p⁶3s¹ or [Ne] 3s₁
Mg electron configuration: 1s²2s²2p⁶3s² or [Ne] 3s²
Be electron configuration: 1s²2s² or [He] 2s²
This is because Na and Mg are right next to each other in the same period (horizontal).
Answer:
group 17 the halogen.as it has 7 electron in its outermost ring
Answer:
The correct answer is option c.
Explanation:
Alkanes with higher molecular mass has higher boiling point.
Thisis because when the molar mass of the alkanes increases the the surface area increases with which van der Waals forces between the molecules of alkane also increase which increases the association of the molecules of with each other which results in increase in boiling point is observed.
The increasing order of the molar mass of the given alkanes;

So out of ethane, pentane and heptane . Heptane has highest molecular mass with higher boiling point value. Where as ethane have the lowest value of boiling point.