3-3 Matter

What Types of Matter Do We Find in Nature? Getting to the Bottom of Thing

Matter is anything that has mass (the amount of material in an object) and takes up space. Matter is found in two chemical forms:

  • Elements: The distinctive building blocks of matter that make up every material substance.

  • Compounds: Two or more different elements held together in fixed proportions by attractive forces called chemical bonds.

What Are Nature’s Building Blocks? Matter’s Bricks

  • Atoms: The smallest unit of matter that exhibits the characteristics of an element.

  • Ions: An electrically charged atom or combination of atoms.

  • Molecules: A combination of two or more atoms of the same or different elements held together by chemical bonds.

What Are Atoms Made of? Looking Inside

Atoms are made up of the following subatomic particles:

  • Positively charged protons (p)

  • Uncharged neutrons (n)

  • Negatively charged electrons (e)

Because atoms are electrically neutral, the atomic number of an atom tells us the number of positively charged protons in its nucleus and the equal number of negatively charged electrons outside its nucleus.

The mass of an atom is described in terms of its mass number: the total number of neutrons and protons in its nucleus.

What Are Ions? Getting Charged Up

Ions form when an atom of an element loses or gains one or more electrons. Thus an ion is an atom or groups of atoms with one or more net positive (+) or negative (−) electrical charges, one for each electron lost or gained.

  • Metals tend to lose one or more of their electrons and form positively charged ions.

  • Other atoms, known as nonmetals, tend to gain one or more electrons and form negatively charged ions

The number of positive or negative charges on an ion is shown as a superscript after the symbol for an atom or a group of atoms.

What Holds the Atoms and Ions in Compounds Together? Giving, Receiving, and Sharing Electrons

Most matter exists as compounds, substances containing atoms or ions of more than one element that are held together by chemical bonds. Chemists use a shorthand chemical formula to show the number of atoms or ions of each type in a compound.

Some compounds are made up of oppositely charged ions and are called ionic compounds. Those made up of molecules of uncharged atoms are called covalent or molecular compounds.

What Are Organic Compounds? Think Carbon

Almost all organic compounds are molecular com- pounds held together by covalent bonds. Organic com- pounds can be either natural (such as carbohydrates, proteins, and fats in natural foods) or synthetic (such as plastics and many drugs made by humans).

The millions of known organic (carbon-based) compounds include the following:

  • Hydrocarbons: compounds of carbon and hydrogen atoms.

  • Chlorinated hydrocarbons: compounds of carbon, hydrogen, and chlorine atoms.

  • Simple carbohydrates (simple sugars): certain types of compounds of carbon, hydrogen, and oxygen atoms.

What Can Molecules Do? Get Together

Larger and more complex organic compounds, essential to life, are composed of macromolecules. Some of these molecules are called polymers, formed when a number of simple organic molecules (called monomers) are linked together.

The three major types of organic molecules are:

  1. Complex carbohydrates such as cellulose and starch, both of which consist of monomers of simple sugars such as glucose linked together

  2. Proteins formed by linkages of monomers called amino acids

  3. Nucleic acids (DNA and RNA) formed by linkages of monomers called nucleotides.

What Are Genes, Chromosomes, and DNA Molecules?

The genetic traits of living organisms are coded for by the organic molecules associated with genes, chromosomes, and DNA. Genes consist of specific sequences of nucleotides in a DNA molecule.

Chromosomes are combinations of genes that make up a single DNA molecule, together with a number of proteins. Each chromosome typically contains thousands of genes.

The genome of a species is made up of the entire sequence of DNA “letters” or base pairs that combine to “spell out” the chromosomes in typical members of each species.

What Are Inorganic Compounds? The Rest of the World’s Compounds

Inorganic compounds do not have carbon–carbon or carbon–hydrogen bonds.

Examples: nitrous oxide (N2O), nitric oxide (NO), carbon monoxide (CO), carbon dioxide (CO2), nitrogen dioxide (NO2), sulphur dioxide (SO2), ammonia (NH3)

What Are Four States of Matter? Let’s Get Physical

The atoms, ions, and molecules that make up matter are found in three physical states: solid, liquid, and gas. The three physical states of any sample of matter differ in the spacing and orderliness of its atoms, ions, or molecules. A solid has the most compact and orderly arrangement and a gas the least compact and orderly arrangement. Liquids are somewhere in between.

A fourth state of matter is called plasma. It is a high-energy mixture of roughly equal numbers of positively charged ions and negatively charged electrons. A plasma forms when enough energy is applied to strip electrons away from the nuclei of atoms.

What Is Matter Quality? Matter Usefulness

Matter quality is a measure of how useful a form of matter is to us as a resource, based on its availability and concentration.

High- quality matter is concentrated, usually is found near the Earth’s surface, and has great potential for use as a material resource. Low-quality matter is dilute, often is deep underground or dispersed in the ocean or the atmosphere, and usually has little potential for use as a material resource.

Material efficiency, or resource productivity, is the total amount of material needed to produce each unit of goods or services.