Question

What is the most abundant element on the earth in terms of mass? Where are several places where this element is commonly found?

Short answer

The most abundant element on Earth in terms of mass is oxygen, making up approximately 46.6% of the Earth's crust. Oxygen is commonly found in the Earth's atmosphere, water (H₂O), minerals such as silicates and oxides, living organisms as a component of organic molecules, and in rocks and soil formations like granite.

Step-by-step solution

Identify the most abundant element

The most abundant element on Earth in terms of mass is oxygen. Approximately 46.6% of the Earth's crust is made up of oxygen.

List places where oxygen is commonly found

Several places where oxygen is commonly found include: 1. Earth's atmosphere: Oxygen comprises about 21% of the Earth's atmosphere by volume. It is essential for human survival, as we breathe in oxygen for cellular respiration. 2. Water: Oxygen is one of the components of water (H₂O), which covers about 71% of the Earth's surface. It is also found in both fresh and saltwater bodies such as rivers, lakes, and oceans. 3. Minerals: Oxygen is a component of many minerals found in the Earth's crust, such as silicates (which include quartz and feldspar) and oxides (such as hematite and magnetite). 4. Living organisms: Oxygen is an essential component of organic molecules found in living organisms, including carbohydrates, proteins, and fats. It is also a key element in cellular respiration, which helps to produce energy for the cells. 5. Rocks and soil: Oxygen is present in various rock and soil formations, often combined with other elements to form mineral compounds. For example, granite is a common rock composed of oxygen, silicon, aluminum, and other elements.

Key concepts

Elemental Abundance

When we look at the Earth's composition, we find that a particular element dominates by mass. This element is oxygen, which accounts for roughly 46.6% of the Earth's crust. Its prominence is due to its involvement in multiple compounds that form the world around us.

For example, oxygen readily combines with silicon to create silicates, the most common group of minerals on our planet. Oxygen's ability to bond with a wide variety of other elements, forming stable compounds, contributes significantly to its abundance. Additionally, oxygen is also essential for life, as it is a fundamental component of the biological processes within all living organisms. Understanding elemental abundance provides insight into the composition of planets and the building blocks of our environment.

Oxygen in Earth's atmosphere

Oxygen plays a critical role in Earth's atmosphere, accounting for about 21% of its volume. This balance is essential for life as we know it; without this specific concentration, humans and many other organisms wouldn't be able to survive.

Photosynthesis by plants and phytoplankton is a significant source of atmospheric oxygen. During this process, these organisms convert carbon dioxide and water into glucose and oxygen, using sunlight as energy. On a geological timescale, the atmospheric oxygen levels have fluctuated, but currently, it remains at a life-supporting level.

Chemical composition of water

Water, with its simple H₂O formula, is another arena where we find the most abundant element on Earth - oxygen. Each water molecule consists of two hydrogen atoms bonded to a single oxygen atom.

Covering about 71% of the Earth's surface, water is omnipresent in oceans, rivers, lakes, and even within living organisms, reinforcing the significance of oxygen on Earth. It is this molecular composition that endows water with unique properties, such as its ability to act as a universal solvent, its high specific heat capacity, and its cohesive and adhesive behaviors. These properties are essential for supporting the Earth's diverse ecosystems.

Minerals containing oxygen

The Earth's crust is replete with minerals that contain oxygen. Silicates are the most common group, including minerals like quartz and feldspar. These are silicon-oxygen compounds that make up a significant portion of the crust.

Oxides, another group of oxygen-containing minerals, include hematite and magnetite, which are essential sources of iron. Many rocks such as granite are composed of several different minerals and thus contain a substantial amount of oxygen. Through the process of weathering, these minerals break down and release oxygen back into the environment, contributing to the biogeochemical cycles that sustain our planet.