Valence Electrons of Elements (Simplified) - Online Tutor, Practice Problems & Exam Prep

Main group elements have valence electrons equal to their group number, influencing chemical bonding. For instance, aluminum in group 3 has 3 valence electrons. Chlorine, with an atomic number of 17, has 7 valence electrons and 10 inner core electrons. The total number of electrons in a neutral atom is the sum of valence and inner core electrons, represented as:

$\mathrm{Total\; Electrons}=\mathrm{Valence\; Electrons}+\mathrm{Inner\; Core\; Electrons}$

Valence Electrons of Elements (Simplified) Concept 1

Now for main group elements, we're going to say that the number of valence electrons that they possess equals their group number. For example, aluminum is in group 3A, so it has 3 valence electrons. These valence electrons are the outer shell electrons involved in forming chemical bonds. Besides the valence electrons, all the remaining electrons are called your inner core electrons. These are the electrons that are not valence electrons.

We're going to say here that your total number of electrons, which is connected to your atomic number for a neutral element, equals your valence electrons plus your inner core electrons. So here if we take a look at chlorine, chlorine has an atomic number of 17. When it is neutral, it has 17 protons, but more importantly 17 electrons. It is in group 7A, so that would mean out of the 17 total electrons, 7 of them are valence electrons. We can see here with this representation of the chlorine atom. We have here our 3rd shell, so n = 3, and in this 3rd shell we have our 7 valence electrons, 1,2,3,4,5,6,7. The remaining 10 electrons are in shells 2 and 1. They total up to a total of 10 electrons.

For chlorine, we'd see that we have our 7 valence electrons in the outer shell with all the remaining electrons serving as our inner core electrons.

Valence Electrons of Elements (Simplified) Example 1

Here it says, how many inner core and valence electrons would a silicon atom possess? So, an atom means that it's a neutral element, and when we look, silicon has an atomic number of 14 on the periodic table. So remember, your atomic number, which is connected to your total number of electrons equals your valence electrons, which for a main group element is just your group number, plus your inner core electrons. Here, the atomic number, again, we said is 14. Silicon is in group 4a on the periodic table. Since it's in group 4a, it has 4 valence electrons. So we already know we have 4 valence electrons. And all we have to do here to find the number of inner core electrons is subtract 4 from both sides, and what's left is 10. That 10 would equal the number of inner core electrons. So, we'd say that the silicon atom has 4 valence electrons in group 4a, and it has 10 inner core electrons.

How many valence electrons does the carbon atom possess?

• A. 4
• B. 2
• C. 6
• D. 3

How many inner core and valence electrons does the nitrogen atom possess?

• A. inner core = 4; valence = 3
• B. inner core = 2; valence = 3
• C. inner core = 2; valence = 5
• D. inner core = 4; valence = 5

Here’s what students ask on this topic:

How do you determine the number of valence electrons in an element?

To determine the number of valence electrons in a main group element, you can look at its group number on the periodic table. For example, elements in Group 1 have 1 valence electron, elements in Group 2 have 2 valence electrons, and so on up to Group 8 (or 18 in the modern IUPAC numbering), which have 8 valence electrons. These valence electrons are the outermost electrons and are involved in chemical bonding.

What is the relationship between valence electrons and chemical bonding?

Valence electrons are the outermost electrons of an atom and play a crucial role in chemical bonding. They are the electrons that are involved in forming bonds with other atoms. Atoms tend to bond in such a way that they achieve a full outer shell of valence electrons, often following the octet rule, which states that atoms are most stable when they have eight valence electrons. This can be achieved through sharing, losing, or gaining electrons.

How many valence electrons does chlorine have?

Chlorine has 7 valence electrons. It is located in Group 7A (or Group 17 in the modern IUPAC numbering) of the periodic table. With an atomic number of 17, chlorine has a total of 17 electrons in a neutral atom. Out of these, 7 are in the outermost shell, making them the valence electrons.

What is the difference between valence electrons and inner core electrons?

Valence electrons are the electrons in the outermost shell of an atom and are involved in chemical bonding. Inner core electrons, on the other hand, are the electrons that reside in the inner shells of an atom. They do not participate in chemical bonding and are closer to the nucleus. The total number of electrons in a neutral atom is the sum of its valence electrons and inner core electrons.

How do you calculate the total number of electrons in a neutral atom?

The total number of electrons in a neutral atom is equal to its atomic number, which is the number of protons in the nucleus. For example, chlorine has an atomic number of 17, so a neutral chlorine atom has 17 electrons. The total number of electrons can be expressed as the sum of valence electrons and inner core electrons: $\mathrm{Total} \mathrm{Electrons}=\mathrm{Valence} \mathrm{Electrons}+\mathrm{Inner} \mathrm{Core} \mathrm{Electrons}$.