Atoms and Elements

The chemical formula for ammonia is NH3, consisting of one nitrogen atom and three hydrogen atoms.

Milk is well known for being a dietary source of calcium, which is a chemical element essential for bone health.

Bananas are a well-known dietary source of potassium, which is a chemical element.

The chemical symbol for iron is Fe, derived from the Latin word ferrum.

The chemical symbol for gold is Au, derived from the Latin word aurum.

C6H12O6 is the chemical formula for glucose, a simple sugar that serves as a primary energy source for living organisms.

Semimetals, also known as metalloids, exhibit properties that are intermediate between those of metals and nonmetals.

Hydrocarbons are organic compounds consisting entirely of hydrogen and carbon, and they are widely used as fuels because they release energy when burned.

DNA (deoxyribonucleic acid) is a type of nucleic acid that carries genetic information.

Proteins are essential macronutrients that play a key role in building and repairing body tissues, including muscle.

Carbohydrates are the body's primary and preferred source of quick energy.

The top three elements in the Earth's crust by mass are oxygen, silicon, and aluminum. Iron is the fourth most abundant element, not one of the top three.

The atomic number, which is the number displayed above each element on the periodic table, represents the number of protons in the nucleus of an atom of that element.

The three classical states of matter represented on the periodic table at room temperature are solid, liquid, and gas. While plasma is a fourth state, it is not typically shown in standard periodic table representations.

Dmitri Mendeleyev is credited with creating the first widely recognized periodic table of elements.

The ancient Greeks believed the world was composed of four elements: earth, air, fire, and water. Oxygen is a modern chemical element discovered much later.

Gerd Binnig and Heinrich Rohrer invented the Scanning Tunneling Microscope (STM) in 1981, which allowed for the imaging of individual atoms.

A compound is a substance formed when two or more chemical elements are chemically bonded together.

The nucleus of an atom is composed of protons and neutrons, while electrons orbit the nucleus.

A neutron is a subatomic particle that carries no electric charge, meaning it is neutral.

Electrons are subatomic particles that carry a negative electric charge and are found in the space surrounding the nucleus.

Protons are subatomic particles located in the nucleus that carry a positive electric charge.

The nucleus is the dense, positively charged central core of an atom.

An atom is defined as the smallest unit of an element that retains the chemical properties of that element.