Question

How many electrons are in \(p\) orbitals in an atom of gallium?

Short answer

Gallium has 1 electron in its 4p orbital.

Step-by-step solution

Identify Gallium's Atomic Number

First, you need to determine the atomic number of gallium (Ga), which is the number of protons in its nucleus. The atomic number is also equal to the number of electrons in a neutral atom. Gallium has an atomic number of 31, meaning it has 31 electrons.

Write Out Electron Configuration

Next, write out the electron configuration for gallium. The configuration up to the previous noble gas (argon) is [Ar]. Continuing from there, the electrons fill up in the following order: 4s^{2} 3d^{10} 4p^{1}. The superscripts indicate the number of electrons in each orbital.

Count Electrons in p Orbitals

From the electron configuration, identify the electrons in the p orbitals. For gallium, the electrons in p orbitals are those in the 4p subshell, which has 1 electron. There are no other p electrons because earlier p orbitals (such as those in the third energy level) are completely filled and count towards earlier elements.

Key concepts

Atomic Number

The atomic number of an element is a fundamental concept in chemistry that describes the number of protons in the nucleus of an atom. It is an essential identifier for each element on the periodic table and also determines the number of electrons in a neutral atom. For instance, gallium (Ga) has an atomic number of 31, which tells us that it possesses 31 protons. Given that charged particles are typically balanced in a neutral atom, this also means that there are 31 electrons within a gallium atom.

This information is the first step in understanding the electron configuration of any element. Electron configuration outlines how electrons are distributed among various orbital shells and subshells around the nucleus. By knowing the atomic number, one can begin to predict and map out how electrons fill these orbitals, which is crucial in explaining an element's chemical behavior.

P Orbitals

P orbitals are a set of three dumbbell-shaped regions around the nucleus where electrons are likely to be found. They are part of a larger system of electron orbitals that also includes s, d, and f orbitals. Each p orbital can hold a maximum of two electrons, and electrons in these orbitals display unique characteristics like spin. When discussing p orbitals in electron configuration, elements may have electrons within multiple p subshells across different energy levels.

For example, in the case of gallium, after filling the lower energy s and d orbitals, electrons begin to populate the 4p orbital. However, only one of the three available spots in the 4p subshell is filled in a gallium atom, which we denote as 4p^1 in its electron configuration. Understanding the properties of p orbitals helps in comprehending the chemical behavior and bonding of an atom.

Electron Arrangement

Electron arrangement, or electron configuration, is the distribution of electrons among the various orbitals around an atom's nucleus. This arrangement is governed by a set of principles – namely, the Aufbau principle, the Pauli exclusion principle, and Hund's rule. These principles explain the order in which electrons populate the orbitals, the limitation on the number of electrons that can occupy an orbital, and the way electrons spread out to minimize repulsion within a single orbital, respectively.

The electron arrangement in an atom can be represented using a specific notation that indicates the energy levels, types of orbitals, and the number of electrons in those orbitals. For Gallium, electron configuration up until Argon is denoted as [Ar], and after that, it follows the order of 4s^2 3d^10 4p^1, which shows that it has fully filled s and d orbitals and one electron in a 4p orbital. The precise arrangement of electrons is crucial for predicting the chemical properties and reactivity of an element.