Can isotopes form ions

An ion is an atom that has had electrons added or removed to give an overall electric charge. It is therefore obvious that any isotope of an element can be ionised, as the number of neutrons has no effect on the electronic structure of the atom. Sign up to join this community. The best answers are voted up and rise to the top.

Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. Can an isotope also be an ion? Ask Question. In general it is difficult to make isotopes and involves a lot of energy.

These are termed nuclear reactions. Ions are made during many chemical reactions, when ionic compounds are dissolved in water, or when enough energy is applied to remove electrons.

Ion formation is more common because electrons are on the outside of an atom and more easily added or removed. Much of chemistry deals with the behavior of electrons. Use the atom building simulation and do the following:. Isotopes and Ions Isotopes are versions of a particular element that have different numbers of neutrons.

Ions are atoms or molecules that have lost or gained electrons and have an electrical charge. According to the octet rule, elements are most stable when their outermost shell is filled with electrons. This is because it is energetically favorable for atoms to be in that configuration. However, since not all elements have enough electrons to fill their outermost shells, atoms form chemical bonds with other atoms, which helps them obtain the electrons they need to attain a stable electron configuration.

When two or more atoms chemically bond with each other, the resultant chemical structure is a molecule. The familiar water molecule, H 2 O, consists of two hydrogen atoms and one oxygen atom, which bond together to form water.

Atoms can form molecules by donating, accepting, or sharing electrons to fill their outer shells. Atoms bond to form molecules : Two or more atoms may bond with each other to form a molecule. When two hydrogens and an oxygen share electrons via covalent bonds, a water molecule is formed. The substances used in the beginning of a chemical reaction are called the reactants usually found on the left side of a chemical equation , and the substances found at the end of the reaction are known as the products usually found on the right side of a chemical equation.

An arrow is typically drawn between the reactants and products to indicate the direction of the chemical reaction. For the creation of the water molecule shown above, the chemical equation would be:. An example of a simple chemical reaction is the breaking down of hydrogen peroxide molecules, each of which consists of two hydrogen atoms bonded to two oxygen atoms H 2 O 2.

The reactant hydrogen peroxide is broken down into water H 2 O , and oxygen, which consists of two bonded oxygen atoms O 2. In the equation below, the reaction includes two hydrogen peroxide molecules and two water molecules. This is an example of a balanced chemical equation, wherein the number of atoms of each element is the same on each side of the equation.

According to the law of conservation of matter, the number of atoms before and after a chemical reaction should be equal, such that no atoms are, under normal circumstances, created or destroyed. Even though all of the reactants and products of this reaction are molecules each atom remains bonded to at least one other atom , in this reaction only hydrogen peroxide and water are representative of a subclass of molecules known as compounds: they contain atoms of more than one type of element.

Molecular oxygen, on the other hand, consists of two doubly bonded oxygen atoms and is not classified as a compound but as an element. Some chemical reactions, such as the one shown above, can proceed in one direction until the reactants are all used up.

The equations that describe these reactions contain a unidirectional arrow and are irreversible. Reversible reactions are those that can go in either direction. In reversible reactions, reactants are turned into products, but when the concentration of product goes beyond a certain threshold, some of these products will be converted back into reactants; at this point, the designations of products and reactants are reversed.

This back and forth continues until a certain relative balance between reactants and products occurs: a state called equilibrium. These situations of reversible reactions are often denoted by a chemical equation with a double headed arrow pointing towards both the reactants and products. If carbonic acid were added to this system, some of it would be converted to bicarbonate and hydrogen ions.

In biological reactions, however, equilibrium is rarely obtained because the concentrations of the reactants or products or both are constantly changing, often with a product of one reaction being a reactant for another.

To return to the example of excess hydrogen ions in the blood, the formation of carbonic acid will be the major direction of the reaction. However, the carbonic acid can also leave the body as carbon dioxide gas via exhalation instead of being converted back to bicarbonate ion, thus driving the reaction to the right by the chemical law known as law of mass action.

These reactions are important for maintaining the homeostasis of our blood. Interactive: What is a Chemical Reaction? Press run, then try heating and cooling the atoms to see how temperature affects the balance between bond formation and breaking.

Ionic bonds are attractions between oppositely charged atoms or groups of atoms where electrons are donated and accepted. Some atoms are more stable when they gain or lose an electron or possibly two and form ions. This results in a full outermost electron shell and makes them energetically more stable. Now, because the number of electrons does not equal the number of protons, each ion has a net charge. Cations are positive ions that are formed by losing electrons as the number of protons is now greater than the number of electrons.

Negative ions are formed by gaining electrons and are called anions wherein there are more electrons than protons in a molecule. For example, the anion of chlorine is called chloride, and the anion of sulfur is called sulfide. This movement of electrons from one element to another is referred to as electron transfer. As illustrated, sodium Na only has one electron in its outer electron shell. It takes less energy for sodium to donate that one electron than it does to accept seven more electrons to fill the outer shell.

When sodium loses an electron, it will have 11 protons, 11 neutrons, and only 10 electrons. It is now referred to as a sodium ion. Chlorine Cl in its lowest energy state called the ground state has seven electrons in its outer shell. Again, it is more energy efficient for chlorine to gain one electron than to lose seven. Therefore, it tends to gain an electron to create an ion with 17 protons, 17 neutrons, and 18 electrons.

This gives it a net charge of -1 since there are now more electrons than protons. It is now referred to as a chloride ion. In this example, sodium will donate its one electron to empty its shell, and chlorine will accept that electron to fill its shell. Both ions now satisfy the octet rule and have complete outer shells.

These transactions can normally only take place simultaneously; in order for a sodium atom to lose an electron, it must be in the presence of a suitable recipient like a chlorine atom.

Electron Transfer Between Na and Cl : In the formation of an ionic compound, metals lose electrons and nonmetals gain electrons to achieve an octet. In this example, sodium loses one electron to empty its shell and chlorine accepts that electron to fill its shell.

Ionic bonds are formed between ions with opposite charges. For instance, positively charged sodium ions and negatively charged chloride ions bond together to form sodium chloride, or table salt, a crystalline molecule with zero net charge. The attractive force holding the two atoms together is called the electromagnetic force and is responsible for the attraction between oppositely charged ions. Certain salts are referred to in physiology as electrolytes including sodium, potassium, and calcium.

Electrolytes are ions necessary for nerve impulse conduction, muscle contractions, and water balance. Many sports drinks and dietary supplements provide these ions to replace those lost from the body via sweating during exercise. Covalent bonds result from a sharing of electrons between two atoms and hold most biomolecules together.

The octet rule can be satisfied by the sharing of electrons between atoms to form covalent bonds. These bonds are stronger and much more common than are ionic bonds in the molecules of living organisms. Covalent bonds are commonly found in carbon-based organic molecules, such as DNA and proteins.

One, two, or three pairs of electrons may be shared between two atoms, making single, double, and triple bonds, respectively. The more covalent bonds between two atoms, the stronger their connection. Thus, triple bonds are the strongest.

The strength of different levels of covalent bonding is one of the main reasons living organisms have a difficult time in acquiring nitrogen for use in constructing nitrogenous molecules, even though molecular nitrogen, N 2 , is the most abundant gas in the atmosphere. Molecular nitrogen consists of two nitrogen atoms triple bonded to each other.

The resulting strong triple bond makes it difficult for living systems to break apart this nitrogen in order to use it as constituents of biomolecules, such as proteins, DNA, and RNA. The formation of water molecules is an example of covalent bonding.

The hydrogen and oxygen atoms that combine to form water molecules are bound together by covalent bonds. The electron from the hydrogen splits its time between the incomplete outer shell of the hydrogen atom and the incomplete outer shell of the oxygen atom. In return, the oxygen atom shares one of its electrons with the hydrogen atom, creating a two-electron single covalent bond.

To completely fill the outer shell of oxygen, which has six electrons in its outer shell, two electrons one from each hydrogen atom are needed. Each hydrogen atom needs only a single electron to fill its outer shell, hence the well-known formula H 2 O. The electrons that are shared between the two elements fill the outer shell of each, making both elements more stable. There are two types of covalent bonds: polar and nonpolar.

In a polar covalent bond, the electrons are unequally shared by the atoms because they are more attracted to one nucleus than the other. The relative attraction of an atom to an electron is known as its electronegativity: atoms that are more attracted to an electron are considered to be more electronegative. This partial charge is known as a dipole; this is an important property of water and accounts for many of its characteristics.

The dipole in water occurs because oxygen has a higher electronegativity than hydrogen, which means that the shared electrons spend more time in the vicinity of the oxygen nucleus than they do near the nucleus of the hydrogen atoms. Polar and Nonpolar Covalent Bonds : Whether a molecule is polar or nonpolar depends both on bond type and molecular shape. Both water and carbon dioxide have polar covalent bonds, but carbon dioxide is linear, so the partial charges on the molecule cancel each other out.

Nonpolar covalent bonds form between two atoms of the same element or between different elements that share electrons equally. For example, molecular oxygen O 2 is nonpolar because the electrons will be equally distributed between the two oxygen atoms. The four bonds of methane are also considered to be nonpolar because the electronegativies of carbon and hydrogen are nearly identical.

Not all bonds are ionic or covalent; weaker bonds can also form between molecules. Two types of weak bonds that frequently occur are hydrogen bonds and van der Waals interactions.

Without these two types of bonds, life as we know it would not exist. Hydrogen bonds provide many of the critical, life-sustaining properties of water and also stabilize the structures of proteins and DNA, the building block of cells. Individual hydrogen bonds are weak and easily broken; however, they occur in very large numbers in water and in organic polymers, and the additive force can be very strong. Some elements—such as carbon, potassium, and uranium—have naturally occurring isotopes.

Carbon contains six protons, six neutrons, and six electrons; therefore, it has a mass number of 12 six protons and six neutrons. Carbon contains six protons, eight neutrons, and six electrons; its atomic mass is 14 six protons and eight neutrons. These two alternate forms of carbon are isotopes. Some isotopes may emit neutrons, protons, and electrons, and attain a more stable atomic configuration lower level of potential energy ; these are radioactive isotopes, or radioisotopes.

Carbon Dating Carbon is normally present in the atmosphere in the form of gaseous compounds like carbon dioxide and methane. Carbon 14 C is a naturally occurring radioisotope that is created in the atmosphere from atmospheric 14 N nitrogen by the addition of a neutron and the loss of a proton because of cosmic rays. This is a continuous process, so more 14 C is always being created. As a living organism incorporates 14 C initially as carbon dioxide fixed in the process of photosynthesis, the relative amount of 14 C in its body is equal to the concentration of 14 C in the atmosphere.

When an organism dies, it is no longer ingesting 14 C, so the ratio between 14 C and 12 C will decline as 14 C decays gradually to 14 N by a process called beta decay—electrons or positrons emission. This decay emits energy in a slow process. After approximately 5, years, half of the starting concentration of 14 C will convert back to 14 N. We call the time it takes for half of the original concentration of an isotope to decay back to its more stable form its half-life. Because the half-life of 14 C is long, scientists use it to date formerly living objects such as old bones or wood.

Comparing the ratio of the 14 C concentration in an object to the amount of 14 C in the atmosphere, scientists can determine the amount of the isotope that has not yet decayed. On the basis of this amount, Figure shows that we can calculate the age of the material, such as the pygmy mammoth, with accuracy if it is not much older than about 50, years.

Other elements have isotopes with different half lives. For example, 40 K potassium has a half-life of 1. Through the use of radiometric dating, scientists can study the age of fossils or other remains of extinct organisms to understand how organisms have evolved from earlier species. Link to Learning To learn more about atoms, isotopes, and how to tell one isotope from another, run the simulation. The periodic table organizes and displays different elements.

Devised by Russian chemist Dmitri Mendeleev — in , the table groups elements that, although unique, share certain chemical properties with other elements.

The properties of elements are responsible for their physical state at room temperature: they may be gases, solids, or liquids. Elements also have specific chemical reactivity , the ability to combine and to chemically bond with each other. In the periodic table in Figure , the elements are organized and displayed according to their atomic number and are arranged in a series of rows and columns based on shared chemical and physical properties.

Looking at carbon, for example, its symbol C and name appear, as well as its atomic number of six in the upper left-hand corner and its atomic mass of The periodic table groups elements according to chemical properties.

Atoms that chemically react and bond to each other form molecules. Molecules are simply two or more atoms chemically bonded together. Logically, when two atoms chemically bond to form a molecule, their electrons, which form the outermost region of each atom, come together first as the atoms form a chemical bond. Note that there is a connection between the number of protons in an element, the atomic number that distinguishes one element from another, and the number of electrons it has.

In all electrically neutral atoms, the number of electrons is the same as the number of protons. Thus, each element, at least when electrically neutral, has a characteristic number of electrons equal to its atomic number. In , Danish scientist Niels Bohr — developed an early model of the atom. The Bohr model shows the atom as a central nucleus containing protons and neutrons, with the electrons in circular orbitals at specific distances from the nucleus, as Figure illustrates.

These orbits form electron shells or energy levels, which are a way of visualizing the number of electrons in the outermost shells.

Electrons fill orbitals in a consistent order: they first fill the orbitals closest to the nucleus, then they continue to fill orbitals of increasing energy further from the nucleus.

If there are multiple orbitals of equal energy, they fill with one electron in each energy level before adding a second electron. Under standard conditions, atoms fill the inner shells first, often resulting in a variable number of electrons in the outermost shell. The innermost shell has a maximum of two electrons but the next two electron shells can each have a maximum of eight electrons. This is known as the octet rule , which states, with the exception of the innermost shell, that atoms are more stable energetically when they have eight electrons in their valence shell , the outermost electron shell.

Figure shows examples of some neutral atoms and their electron configurations. Notice that in Figure , helium has a complete outer electron shell, with two electrons filling its first and only shell. Similarly, neon has a complete outer 2n shell containing eight electrons. In contrast, chlorine and sodium have seven and one in their outer shells, respectively, but theoretically they would be more energetically stable if they followed the octet rule and had eight. An atom may give, take, or share electrons with another atom to achieve a full valence shell, the most stable electron configuration.

Looking at this figure, how many electrons do elements in group 1 need to lose in order to achieve a stable electron configuration? How many electrons do elements in groups 14 and 17 need to gain to achieve a stable configuration? Elements in groups 14 and 17 need to gain four and one electrons, respectively, to achieve a stable configuration.

The periodic table is arranged in columns and rows based on the number of electrons and their location. The group 18 atoms helium He , neon Ne , and argon Ar all have filled outer electron shells, making it unnecessary for them to share electrons with other atoms to attain stability. They are highly stable as single atoms.

Because they are non reactive, scientists coin them inert or noble gases. Compare this to the group 1 elements in the left-hand column. These elements, including hydrogen H , lithium Li , and sodium Na , all have one electron in their outermost shells. That means that they can achieve a stable configuration and a filled outer shell by donating or sharing one electron with another atom or a molecule such as water. Hydrogen will donate or share its electron to achieve this configuration, while lithium and sodium will donate their electron to become stable.

As a result of losing a negatively charged electron, they become positively charged ions. Group 17 elements, including fluorine and chlorine, have seven electrons in their outmost shells, so they tend to fill this shell with an electron from other atoms or molecules, making them negatively charged ions. Group 14 elements, of which carbon is the most important to living systems, have four electrons in their outer shell allowing them to make several covalent bonds discussed below with other atoms.

Although useful to explain the reactivity and chemical bonding of certain elements, the Bohr model does not accurately reflect how electrons spatially distribute themselves around the nucleus.

They do not circle the nucleus like the earth orbits the sun, but we find them in electron orbitals. These relatively complex shapes result from the fact that electrons behave not just like particles, but also like waves.

Mathematical equations from quantum mechanics, which scientists call wave functions, can predict within a certain level of probability where an electron might be at any given time. Scientists call the area where an electron is most likely to be found its orbital.

Within each electron shell are subshells, and each subshell has a specified number of orbitals containing electrons. The letter s, p , d , and f designate the subshells. The s subshell is spherical in shape and has one orbital. Principal shell 1n has only a single s orbital, which can hold two electrons.

Principal shell 2n has one s and one p subshell, and can hold a total of eight electrons. The p subshell has three dumbbell-shaped orbitals, as Figure illustrates. Subshells d and f have more complex shapes and contain five and seven orbitals, respectively. We do not show these in the illustration. Principal shell 3n has s , p , and d subshells and can hold 18 electrons. Principal shell 4n has s , p , d and f orbitals and can hold 32 electrons.