Question

1. which of the following shows a correct lewis dot structure? •al• •si• •y •n:

Explanation:

Step1: Recall valence - electron rules

Lewis dot structures are based on the number of valence electrons of an atom. Aluminum (Al) has 3 valence electrons, silicon (Si) has 4 valence electrons, yttrium (Y) has 3 valence electrons, and nitrogen (N) has 5 valence electrons.

Step2: Analyze each option

• For Al: The correct Lewis dot structure should have 3 dots around the symbol. The given $\cdot\ddot{Al}\cdot$ is incorrect as it shows 4 dots.
• For Si: The correct Lewis dot structure should have 4 dots around the symbol. The given $\cdot Si\cdot$ is correct as it shows 4 dots representing its 4 valence electrons.
• For Y: The correct Lewis dot structure should have 3 dots around the symbol. The given $\dot{Y}$ shows only 1 dot, so it is incorrect.
• For N: The correct Lewis dot structure should have 5 dots (3 single and 1 lone - pair). The given $\cdot\ddot{N}:$ is incorrect as the dot - placement and number of dots are not in accordance with the 5 - valence - electron rule for nitrogen.

Answer:

$\cdot Si\cdot$