Question

how many valence electrons does si have?
②nitrogen n-14
p=
n=
e=
draw nitrogen
valence electrons?

Explanation:

Step1: Determine Si's position

Silicon (Si) is in group 14 of the periodic table.

Step2: Relate group to valence electrons

For main - group elements, the number of valence electrons is equal to the group number (for groups 1 - 2 and 13 - 18). Group 14 elements have 4 valence electrons. So Si has 4 valence electrons.

For Nitrogen (N):

Step1: Determine N's position

Nitrogen is in group 15 of the periodic table.

Step2: Relate group to valence electrons

For main - group elements, group 15 elements have 5 valence electrons. So N has 5 valence electrons.

To draw the Bohr model of Nitrogen (N - 14):

Step1: Find number of protons, neutrons, electrons

• Protons (P): Atomic number of N is 7, so \( P = 7 \).
• Neutrons (N): Mass number (14) - atomic number (7), so \( N=14 - 7=7 \).
• Electrons (E): In a neutral atom, electrons = protons, so \( E = 7 \).

Step2: Draw energy levels

• First energy level (n = 1) can hold a maximum of 2 electrons.
• Second energy level (n = 2) can hold a maximum of 8 electrons, but we have \( 7-2 = 5 \) electrons left for the second level. So the Bohr model has 2 electrons in the first shell and 5 electrons in the second shell, with 7 protons and 7 neutrons in the nucleus.

Answer:

Silicon (Si) has 4 valence electrons.
Nitrogen (N) has 5 valence electrons.
Bohr model of N - 14: Nucleus with 7 protons and 7 neutrons, first energy level with 2 electrons, second energy level with 5 electrons.