Question

1. choose the best answer.

which of these element groups always have two valence electrons?
transition
alkaline earth
alkali

1. choose the best answer.

elements in a ______ have similar properties due to valence electrons.
block
configuration
period
group

Explanation:

• Question 5: Alkaline earth metals (Group 2 elements) have 2 valence electrons. Transition metals can have variable valence electrons (usually 1 - 2, but can involve \(d\) - electrons in bonding). Alkali metals (Group 1) have 1 valence electron.
• Question 6: Elements in a group (vertical column in the periodic table) have the same number of valence electrons, which leads to similar chemical properties. Elements in a period (horizontal row) have valence electrons in the same principal energy level but different numbers of valence electrons. Electron - block (e.g., \(s\) - block, \(p\) - block) and configuration are not the terms that directly relate to similar properties due to valence electrons as precisely as the term "group".

Answer:

1. alkaline earth
2. group