The Role of Atomic Number and Mass Number

Oct 13, 2025 by wbrum.org 38 views

Sodium is an element with the atomic number 11, which means it has 11 protons in its atomic nucleus. The atomic mass of sodium is 23, indicating that it has a total of 23 nucleons (protons and neutrons) in its nucleus. When sodium loses an electron to form a positive ion, it becomes a sodium ion with the symbol $${ }_{11}^{23} Na^{+}$$.

The Role of Atomic Number and Mass Number

The atomic number of an element is a unique identifier that represents the number of protons in the nucleus of an atom. In the case of sodium, the atomic number is 11, which means it has 11 protons. The mass number, on the other hand, represents the total number of nucleons (protons and neutrons) in the nucleus. For sodium, the mass number is 23, indicating that it has a total of 23 nucleons.

Electrons in a Sodium Ion

When sodium loses an electron to form a positive ion, it becomes a sodium ion with the symbol $${ }_{11}^{23} Na^{+}$$. The question asks how many electrons are in this sodium ion. To answer this question, we need to understand the relationship between the atomic number and the number of electrons in an atom.

The Octet Rule

The octet rule states that atoms tend to gain, lose, or share electrons to achieve a full outer energy level, which typically consists of eight electrons. In the case of sodium, it has 11 electrons in its neutral state. When sodium loses an electron to form a positive ion, it becomes a sodium ion with 10 electrons.

Conclusion

Based on the understanding of the atomic number and the octet rule, we can conclude that a sodium ion $${ }_{11}^{23} Na^{+}$$ has 10 electrons.

Answer

The correct answer is B. 10.

Additional Information

The atomic number of sodium is 11, which means it has 11 protons in its atomic nucleus.
The mass number of sodium is 23, indicating that it has a total of 23 nucleons in its nucleus.
When sodium loses an electron to form a positive ion, it becomes a sodium ion with 10 electrons.
The octet rule states that atoms tend to gain, lose, or share electrons to achieve a full outer energy level, which typically consists of eight electrons.
Frequently Asked Questions about Sodium Ion =====================================================

Q: What is the atomic number of sodium?

A: The atomic number of sodium is 11, which means it has 11 protons in its atomic nucleus.

Q: What is the mass number of sodium?

A: The mass number of sodium is 23, indicating that it has a total of 23 nucleons (protons and neutrons) in its nucleus.

Q: How many electrons does a neutral sodium atom have?

A: A neutral sodium atom has 11 electrons.

Q: How many electrons does a sodium ion have?

A: A sodium ion has 10 electrons.

Q: What is the symbol for a sodium ion?

A: The symbol for a sodium ion is $${ }_{11}^{23} Na^{+}$$.

Q: What is the octet rule?

A: The octet rule states that atoms tend to gain, lose, or share electrons to achieve a full outer energy level, which typically consists of eight electrons.

Q: Why does sodium lose an electron to form a positive ion?

A: Sodium loses an electron to form a positive ion because it tends to gain, lose, or share electrons to achieve a full outer energy level, which typically consists of eight electrons.

Q: What is the relationship between the atomic number and the number of electrons in an atom?

A: The atomic number of an element is a unique identifier that represents the number of protons in the nucleus of an atom. In the case of sodium, the atomic number is 11, which means it has 11 protons. The number of electrons in a neutral sodium atom is equal to the atomic number, which is 11.

Q: How many protons does a sodium ion have?

A: A sodium ion has 11 protons.

Q: How many neutrons does a sodium ion have?

A: A sodium ion has 12 neutrons.

Q: What is the difference between a sodium atom and a sodium ion?

A: The main difference between a sodium atom and a sodium ion is that a sodium atom has 11 electrons, while a sodium ion has 10 electrons.

Q: Why is it important to understand the structure of sodium ion?

A: Understanding the structure of sodium ion is important because it helps us understand the chemical properties of sodium and how it reacts with other elements.

Q: What are some common applications of sodium ion?

A: Sodium ion has several common applications, including:

In the production of sodium hydroxide, which is used in the manufacture of paper, soap, and textiles.
In the production of sodium carbonate, which is used in the manufacture of glass, paper, and detergents.
In the production of sodium chloride, which is used as a seasoning and preservative in food.

Q: What are some common hazards associated with sodium ion?

A: Some common hazards associated with sodium ion include:

Fire and explosion hazards due to its reactivity with water.
Corrosion hazards due to its reactivity with certain metals.
Toxicity hazards due to its ability to cause skin and eye irritation.