The element with 34 protons and 36 electrons is Selenium (Se). This specific combination signifies a negatively charged selenium ion, known as an anion.
Identifying the Element: The Role of Protons
The identity of an element is solely determined by the number of protons in its nucleus. This number is known as the atomic number.
- An element with 34 protons has an atomic number of 34.
- Referring to the periodic table, the element with atomic number 34 is Selenium (Se).
Selenium is a nonmetal belonging to Group 16 of the periodic table, also known as the chalcogens. It shares chemical similarities with sulfur and tellurium.
Understanding the Ion: Protons vs. Electrons
While the number of protons defines the element, the number of electrons determines the charge of the atom or ion.
- A neutral atom has an equal number of protons and electrons. For a neutral selenium atom, there would be 34 protons and 34 electrons.
- In this case, there are 34 protons but 36 electrons.
- This means there are 2 more electrons than protons (36 - 34 = 2).
- Since electrons carry a negative charge, an excess of 2 electrons results in a net charge of -2.
- Therefore, the species described is a selenium ion (anion) with a charge of Se²⁻.
This illustrates that while the element itself is selenium, the specific entity is not a neutral atom but an ion formed by gaining electrons.
Key Characteristics of this Species
| Characteristic | Value | Explanation |
|---|---|---|
| Element Name | Selenium | Determined by the number of protons. |
| Element Symbol | Se | The chemical symbol for Selenium. |
| Atomic Number | 34 | The number of protons in the nucleus. |
| Number of Protons | 34 | Defines the element as Selenium. |
| Number of Electrons | 36 | More electrons than protons, indicating an ion. |
| Net Charge | -2 | Calculated as (Protons - Electrons) = (34 - 36) = -2. |
| Species Type | Anion | A negatively charged ion, specifically Se²⁻. |
Why is this Distinction Important?
The difference between a neutral atom and its ion is crucial in chemistry:
- Chemical Behavior: Neutral atoms and their corresponding ions exhibit very different chemical properties and reactivities. For example, a neutral selenium atom might form covalent bonds, while the Se²⁻ ion is typically found in ionic compounds.
- Stability: Elements often gain or lose electrons to achieve a more stable electron configuration, typically resembling that of a noble gas. Selenium (atomic number 34) gains two electrons to achieve the electron configuration of Krypton (atomic number 36), thus forming a stable Se²⁻ ion.
Understanding the balance between protons and electrons is fundamental to comprehending the formation of chemical bonds and the behavior of matter.
