- The attractions between the protons and electrons of atoms can cause an electron to move completely from one atom to the other.
- When an atom loses or gains an electron, it is called an ion.
- The atom that loses an electron becomes a positive ion.
- The atom that gains an electron becomes a negative ion.
- A positive and negative ion attract each other and form an ionic bond.
Students will look at animations and make drawings of the ionic bonding of sodium chloride (NaCl). Students will see that both ionic and covalent bonding start with the attractions of protons and electrons between different atoms. But in ionic bonding, electrons are transferred from one atom to the other and not shared like in covalent bonding. Students will use Styrofoam balls to make models of the ionic bonding in sodium chloride (salt).
Students will be able to explain the process of the formation of ions and ionic bonds.
Download the student activity sheet, and distribute one per student when specified in the activity. The activity sheet will serve as the “Evaluate” component of each 5-E lesson plan.
Be sure you and the students wear properly fitting goggles.
Materials for Each Group
- Black paper
- Cup with salt from evaporated saltwater
- Permanent marker
Materials for Each Student
- 2 small Styrofoam balls
- 2 large Styrofoam balls
- 2 toothpicks
Note: In an ionically bonded substance such as NaCl, the smallest ratio of positive and negative ions bonded together is called a “formula unit” rather than a “molecule.” Technically speaking, the term “molecule” refers to two or more atoms that are bonded together covalently, not ionically. For simplicity, you might want to use the term “molecule” for both covalently and ionically bonded substances.
Show a video of sodium metal reacting with chlorine gas.
Project the video Sodium and chlorine react.
Before starting the video, tell students that chlorine is a greenish poisonous gas and sodium is a shiny, soft, and very reactive metal. But when they react, they form sodium chloride (table salt). Tell students that in the video, the drop of water helps expose the atoms at the surface of the sodium so that they can react with the chlorine. The formation of the salt crystals releases a lot of energy.(Video) Energy Levels, Electrons, and Ionic Bonding
Note: If students ask if the salt they eat is made this way in salt factories, the answer is no. The salt on Earth was produced billions of years ago but probably not from pure chlorine gas and sodium metal. These days, we get salt from mining it from a mineral called halite or from evaporating sea water.
Show an animation to introduce the process of ionic bonding.
Project the animation Ionic bond in sodium chloride.See Also4.3: Sodium Chloride and Ionic BondsHow Is nacl Ionic: And Why Not Covalent, Detailed Facts | Lambda GeeksIs NaCl Ionic or Covalent? - Techiescientist5 Ways to Make Ionic and Covalent Bonds an Approachable Topic
Remind students that in covalent bonding, atoms share electrons. But there is another type of bonding where atoms don’t share, but instead either take or give up electrons. This is called ionic bonding. This animation shows a very simplified model of how sodium and chloride ions are formed.
Note: In order to simplify the model of ionic bonding, a single atom of sodium and chlorine are shown. In reality, the chlorine atom would be bonded to another chlorine atom as part of the gas Cl2. The sodium atom would be one of billions of trillions of sodium atoms bonded together as a solid. The combination of these substances is a complex reaction between the atoms of the two substances. The animation shows single separated atoms to illustrate the idea of how ions and ionic bonds are formed.
Explain what happens during the animation.
Tell students that the attraction of the protons in the sodium and chlorine for the other atom’s electrons brings the atoms closer together. Chlorine has a stronger attraction for electrons than sodium (shown by the thicker arrow). At some point during this process, an electron from the sodium is transferred to the chlorine. The sodium loses an electron and the chlorine gains an electron.
Tell students that when an atom gains or loses an electron, it becomes an ion.
- Sodium loses an electron, leaving it with 11 protons, but only 10 electrons. Since it has 1 more proton than electrons, sodium has a charge of +1, making it a positive ion.
- Chlorine gains an electron, leaving it with 17 protons and 18 electrons. Since it has 1 more electron than protons, chlorine has a charge of −1, making it a negative ion.
- When ions form, atoms gain or lose electrons until their outer energy level is full.
- For example, when sodium loses its one outer electron from the third energy level, the second level becomes the new outer energy level and is full. Since these electrons are closer to the nucleus, they are more tightly held and will not leave.
- When chlorine gains an electron, its third energy level becomes full. An additional electron cannot join, because it would need to come in at the fourth energy level. This far from the nucleus, the electron would not feel enough attraction from the protons to be stable.
- Then the positive sodium ion and negative chloride ion attract each other and form an ionic bond. The ions are more stable when they are bonded than they were as individual atoms.
Have students describe the process of ionic bonding in sodium chloride on their activity sheet.
Give each student an activity sheet.
Have students write a short caption under each picture to describe the process of covalent bonding and answer the first three questions. The rest of the activity sheet will either be completed as a class, in groups, or individually depending on your instructions.
Project the image Ionic bond in sodium chloride.
Review with students the process of ionic bonding covered in the animation.(Video) Introduction to Ionic Bonding and Covalent Bonding
Help students write a short caption beside each picture to describe the process of ionic bonding in sodium and chloride ions.
- Sodium and chlorine atoms are near each other.
- The protons of the two atoms attract the electrons of the other atom. The thicker arrow shows that chlorine has a stronger attraction for electrons than sodium has.
- During the interactions between the atoms, the electron in sodium's outer energy level is transferred to the outer energy level of the chlorine atom.
- Since sodium lost an electron, it has 11 protons, but only 10 electrons. This makes sodium a positive ion with a charge of +1. Since chlorine gained an electron it has 17 protons and 18 electrons. This makes chloride a negative ion with a charge of −1.
- The positive sodium ion and negative chloride ion attract one another. They make an ionic bond and form the ionic compound NaCl.
Show students a model of a sodium chloride crystal and have them identify the ions.
Project the image Sodium chloride crystal.
Review with students the process of ionic bonding covered in the animation so that students will understand why the sodium ions are positive and the chloride ions are negative.
Remind students that the scale of any model of atoms, ions, or molecules is enormous compared to the actual size. In a single grain of salt there are billions of trillions of sodium and chloride ions.
- What ion is the larger ball with the negative charge?
- The chlorine ion.
- What made it negative?
- It gained an electron.
- What is the ion with the positive charge?
- The sodium ion.
- What made it positive?
- It lost an electron.
Have students observe actual sodium chloride crystals and relate their shape to the molecular model.
This two-part activity will help students see the relationship between the arrangement of ions in a model of a sodium chloride crystal and the cubic shape of real sodium chloride crystals.
The day before the lesson, dissolve about 10 grams of salt in 50 mL of water. Use Petri dishes or use scissors to cut down 5 or 6 clear plastic cups to make shallow plastic dishes. Pour enough saltwater to just cover the bottom of each dish (1 for each group). Leave the dishes overnight to evaporate so that new salt crystals will be produced.
Materials for each group
- Black paper
- Cup with salt from evaporated saltwater
- Permanent marker
Materials for each student
- 2 small Styrofoam balls
- 2 large Styrofoam balls
- 2 toothpicks
Procedure, Part 1
Observe sodium chloride crystals.
- Place a few grains of salt on a piece of black paper. Use your magnifier to look closely at the salt.
- Use your magnifier to look at the salt crystals in the cup.
Project the image Cubic sodium chloride.
The image shows both a magnified view of ordinary table salt and a model of the sodium and chloride ions that make up a salt crystal.(Video) GCSE Science Revision Chemistry "Ionic Bonding 1"
Project the animation Sodium Chloride Crystal.
The green spheres represent negatively charged chloride ions and the gray spheres represent positively charged sodium ions.
- What do the photograph, molecular model, and your observations of real salt crystals tell you about the structure of salt?
- In each case, the salt seems to be shaped like a cube.
Have students build a 3-dimensional model of sodium chloride.
Each student will make 1 unit of sodium chloride. Students in each group will put their sodium chloride units together. You can help the groups combine their structures into a class model of a sodium chloride crystal.
Procedure, Part 2
Make NaCl units.
- Use the marker to put a “−” on the large balls which represent chloride ions.
- Use the marker to put a “+” on the small balls, which represent sodium ions.
- Break two toothpicks in half. Use one of the half-toothpicks to connect the centers of the small and large ions together to make a unit of sodium chloride (NaCl). Do the same thing with the other small and large ball.
Use another half-toothpick to connect the two NaCl units in a straight line as shown.
Put NaCl ions together to make one layer of ions.
- Contribute your line of ions to your group and arrange them to make a 4×4 square of ions.
Use half-toothpicks to attach the ends of each line to hold the ions together. You only need to place toothpicks in the balls at the end of each line.
Build a class sodium chloride crystal.
Give your group’s layer of ions to your teacher. Your teacher will stack these to build a model of a sodium chloride crystal.
Point out that anywhere you look on the crystal, a sodium ion and a chloride ion are always surrounded by the oppositely charged ion. These opposite charges hold the ions together in a crystal.
Ask students(Video) The Periodic Table: Atomic Radius, Ionization Energy, and Electronegativity
- Based on the way sodium and chloride ions bond together, why are salt crystals shaped like cubes?
- The size and arrangement of the ions forms a cube on the molecular level. Since the pattern repeats over and over again in the same way, the shape stays the same even when the crystal becomes the normal size that we can see.
Show students how calcium and chlorine atoms bond to form the ionic compound calcium chloride.
Tell students that there is another common substance called calcium chloride (CaCl2). It is the salt that is used on icy sidewalks and roads. Explain that when calcium and chlorine react they produce ions, like sodium and chlorine, but the calcium ion is different from the sodium ion.
- What ions do you think CaCl2 is made of?
- One calcium ion and two chloride ions.
Project the animation Calcium chloride Ionic Bond.
Point out that the calcium loses two electrons, becoming a +2 ion. Each of the two chlorine atoms gains one of these electrons, making them each a −1 ion. Help students realize that 1 calcium ion bonds with 2 chloride ions to form calcium chloride (CaCl2), which is neutral.
Some atoms gain or lose more than 1 electron. Calcium loses 2 electrons when it becomes an ion. When ions come together to form an ionic bond, they always join in numbers that exactly cancel out the positive and negative charge.
Project the image Calcium chloride Ionic Bond.
Review with students the process of ionic bonding covered in the animation.
Have students write a short caption beneath each picture to describe the process of ionic bonding in sodium and chloride ions.
- One calcium and two chlorine are near each other.
- The protons of the calcium atom attract the electrons from the chlorine atom. The protons of the two chlorine atoms attract the electrons from the calcium atom more strongly as shown by the thicker arrows.
- During the interactions between the atoms, the two electrons in calcium's outer energy level are transferred to the outer energy level of each of the chlorine atoms.
- Since calcium lost two electrons, it has 20 protons, but only 18 electrons. This makes calcium a positive ion with a charge of 2+. Since each chlorine atom gained an electron, they each have 17 protons and 18 electrons. This makes each chloride a negative ion with a charge of −1.
- Oppositely charged ions attract each other, forming an ionic bond. The bonded ions are more stable than the individual atoms were.
Four main bonding types are discussed here: ionic, covalent, metallic, and molecular.What is an ionic bond with two suitable examples explain the difference between an ionic and a covalent bond? ›
- Ionic bonds are the bonds formed between a metal and a non-metal while covalent bonds are formed between two nonmetals. - Ionic bonds are formed when there is a high electronegativity difference between the atoms while covalent bonds are formed between the atoms where there is not much electronegativity difference.Is H2O ionic or covalent? ›
Water (H2O), like hydrogen fluoride (HF), is a polar covalent molecule.What kind of element loses electron after ionic bonding? ›
In ionic bonds, the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.How many types are bonds? ›
The Bonds can be categorised into four variants: Corporate Bonds, Municipal Bonds, Government Bonds and Agency Bonds.What is the difference between ionic bond and polar covalent bond Give an example for each one? ›
The only pure covalent bonds occur between identical atoms. Usually, there is some polarity (polar covalent bond) in which the electrons are shared, but spend more time with one atom than the other. Ionic bonds form between a metal and a nonmetal. Covalent bonds form between two nonmetals.What is covalent bond how it is formed explain with example? ›
These electron pairs are known as shared pairs orbonding pairs, and the stable balance of attractive and repulsive forces between atoms, when they share electrons, is known as covalent bonding. example could be "Water, H2O" as it is formed by the share of electrons of hydrogen and oxygen (which are both non-metals).What are 3 examples of an ionic bond? ›
Examples of Ionic Bonds
Some ionic bond examples include: NaCl: sodium chloride. NaBr: sodium bromide. NaF: sodium fluoride.
NH3 is a covalent bond. This is because, Nitrogen and Hydrogen have shared the electron. The main difference between an ionic and covalent bond is ionic bond will donate or accept electron.What type of bond is NaCl? ›
Ionic bonds usually occur between metal and nonmetal ions. For example, sodium (Na), a metal, and chloride (Cl), a nonmetal, form an ionic bond to make NaCl.
Hence, O 2 is a covalent bond.Why are ionic bonds formed? ›
An ionic bond can be formed after two or more atoms loss or gain electrons to form an ion. Ionic bonds occur between metals, losing electrons, and nonmetals, gaining electrons. Ions with opposite charges will attract one another creating an ionic bond.Which pair of elements form an ionic bond? ›
Ionic compounds generally form between elements that are metals and elements that are nonmetals. For example, the metal calcium (Ca) and the nonmetal chlorine (Cl) form the ionic compound calcium chloride (CaCl2).What are bonds example? ›
4 Common Types of Bonds
There are several classes of bonds: Treasury securities are issued by the federal government; municipal bonds are issued by states and local governments; and corporate bonds are issued by companies. Other types of bonds include high-yield bonds, agency securities, and asset-backed securities.
Chemical bonding is one of the most basic fundamentals of chemistry that explains other concepts such as molecules and reactions. Without it, scientists wouldn't be able to explain why atoms are attracted to each other or how products are formed after a chemical reaction has taken place.What is chemical bond example? ›
A chemical bond is a bond that holds atoms together. It is the force that binds ions or molecules together. It helps form a chemical compound. Examples of the chemical compounds that are of special interest to biologists are water, sodium chloride, and carbon dioxide.What is bond value? ›
What Is Bond Valuation? Bond valuation is a technique for determining the theoretical fair value of a particular bond. Bond valuation includes calculating the present value of a bond's future interest payments, also known as its cash flow, and the bond's value upon maturity, also known as its face value or par value.What bond means? ›
A bond represents a promise by a borrower to pay a lender their principal and usually interest on a loan. Bonds are issued by governments, municipalities, and corporations.What is bond explain? ›
What are bonds? A bond is a debt security, similar to an IOU. Borrowers issue bonds to raise money from investors willing to lend them money for a certain amount of time. When you buy a bond, you are lending to the issuer, which may be a government, municipality, or corporation.What are examples of ionic bonds and covalent bonds? ›
- Give two example in each case : ...
- Which one of the following contains ionic, covalent and coordinate bonds? ...
- Why is metallic bonding different from ionic or covalent bonding?
If two atoms have an electronegativity difference of 0.4 or less, they form a non-polar covalent bond. If two atoms have an electronegativity difference between 0.4 and 1.8, they form a polar covalent bond. If two atoms have an electronegativity difference of more than 1.8, they form an ionic bond.What are covalent compounds write any three features and give two examples? ›
Properties of covalent compounds include:
- Have low boiling points and melting points.
- Generally are poor conductors of heat and electricity.
- Exist as brittle solids.
- Single Covalent Bond.
- Double Covalent Bond.
- Triple Covalent Bond.
Single Covalent Bond
Example: The HCL molecule has one Hydrogen atom with one valence electron and one Chlorine atom with seven valence electrons. In this case, a single bond is formed between hydrogen and chlorine by sharing one electron thus completing its octet of one molecule of HCL.
Common examples include sodium, potassium, calcium, chloride, and bicarbonate. These substances are known as electrolytes. Ions can be created using radiation such as x-rays.What are 4 common ionic compounds? ›
- sodium chloride: NaCl, with Na+ and Cl- ions.
- lithium nitride: Li3N, with Li+ and N3- ions.
- magnesium oxide: MgO, with Mg2+ and O2- ions.
- calcium phosphide: Ca3P2, with Ca2+ and P3- ions.
Examples of ions are as follows: H+,Na+,Ca2+,F−,O2−Is co2 ionic bond? ›
Hence, CO2 is not a ionic compound.What type of bond is sugar? ›
Sugar, on the other hand, is composed of carbon, oxygen, and hydrogen and has covalent bonds.What type of bond is water? ›
In the case of water, hydrogen bonds form between neighboring hydrogen and oxygen atoms of adjacent water molecules. The attraction between individual water molecules creates a bond known as a hydrogen bond.
Strong linkages—called covalent bonds—hold together the hydrogen (white) and oxygen (red) atoms of individual H2O molecules. Covalent bonds occur when two atoms—in this case oxygen and hydrogen—share electrons with each other.Why do covalent bonds form? ›
A covalent bond forms when the difference between the electronegativities of two atoms is too small for an electron transfer to occur to form ions. Shared electrons located in the space between the two nuclei are called bonding electrons. The bonded pair is the “glue” that holds the atoms together in molecular units.What type of bond is nh3? ›
Ammonia contains nitrogen and hydrogen, which are both nonmetals. So nitrogen forms three covalent bonds with the three hydrogen present.What type of bond is HCl? ›
The bond between hydrogen and chlorine in HClHCl is a polar covalent bond. It is formed by sharing of an electron pair between the two atoms.What is ionic character? ›
Ionic character refers to the percentage of difference between the electronegativity of two covalently bonded atoms.What are the properties of ionic bond? ›
Properties of Ionic Compounds
Ionic Compounds have high boiling and melting points as they're very strong and require a lot of energy to break. The electrostatic forces of attraction between oppositely charged ions lead to the formation of ions. Ionic compounds form crystals.
ionic bond, also called electrovalent bond, type of linkage formed from the electrostatic attraction between oppositely charged ions in a chemical compound. Such a bond forms when the valence (outermost) electrons of one atom are transferred permanently to another atom.Which element forms both ionic and covalent bonds? ›
Bond between K+ and CN− is ionic where as bond within CN− is covalent. Hence both ionic and covalent bonds are present in KCN.Why ionic compounds are solids? ›
Ionic compounds are made up of oppositely charged ions which are held together by strong electrostatic force of attraction. Due to this reason, they are hard solids. When large pressure is applied , they tend to break into pieces.What forms an ionic compound? ›
Ionic compounds are compounds composed of ions, charged particles that form when an atom (or group of atoms) gains or loses electrons. (A cation is a positively charged ion; an anion is a negatively charged ion.) Covalent or molecular compounds form when elements share electrons in a covalent bond to form molecules.
A bond is ionic if the electronegativity difference between the atoms is great enough that one atom could pull an electron completely away from the other one. That situation is common in compounds that combine elements from the left-hand edge of the periodic table (sodium, potassium, calcium, etc.)Can there be 4 bonds? ›
The fourth bond (quadruple bond) if formed would be pointing away from the two carbons. In order for this bond to exist, the other three bonds need to be tremendously bent and this is energetically very unfeasible. This strain thus resists the formation of the quadruple bond.What are the 4 covalent bonds? ›
In a single bond one pair of electrons is shared, with one electron being contributed from each of the atoms. Double bonds share two pairs of electrons and triple bonds share three pairs of electrons. Bonds sharing more than one pair of electrons are called multiple covalent bonds.What are the 5 types of bonds? ›
There are five main types of bonds: Treasury, savings, agency, municipal, and corporate. Each type of bond has its own sellers, purposes, buyers, and levels of risk vs. return. If you want to take advantage of bonds, you can also buy securities that are based on bonds, such as bond mutual funds.What are the 4 types of bonds in chemistry class 11? ›
- Ionic bonds. -Present between atoms and are forms due to the exchange of valence electrons. -Can occur between both metals and nonmetals. ...
- Covalent bonds. -They involve two atoms, usually nonmetals. ...
- Metallic bonds.
There are four types of chemical bonds essential for life to exist: Ionic Bonds, Covalent Bonds, Hydrogen Bonds, and van der Waals interactions.How are 4 bonds formed? ›
Because carbon has four electrons in its valence shell, it is able to form four covalent bonds with other atoms. When carbon forms four bonds with atoms, the resulting molecule has a tetrahedron shape.How are the 3 types of bonds formed? ›
Ionic bonds are formed when a metal and a nonmetal interact by exchange of electrons; covalent bonds are formed when nonmetal atoms come together to share a few of their valence electrons; and metallic bonding happens when metals interact with one another.What are 5 examples of covalent bonds? ›
Five examples of covalent bonds are hydrogen (H₂), oxygen (O₂), nitrogen (N₂), water (H₂O), and methane(CH₄). 2. What is a covalent bond? A chemical bond involving the sharing of electron pairs between atoms is known as a covalent bond.Do Group 4 elements form covalent bonds? ›
The Group 4A elements have four valence electrons in their highest-energy orbitals (ns2np2). Carbon and silicon can form ionic compounds by gaining four electrons, forming the carbide anion (C4-) and silicide anion (Si4-), but they more frequently form compounds through covalent bonding.
Carbon forms four covalent bonds by sharing its four valence electrons with four univalent atoms, e.g. hydrogen. After the formation of four bonds, carbon attains the electronic configuration of: (1) Helium (2) Neon. (3) Argon (4) Krypton.What are the 7 types of bonds? ›
Treasury bonds, GSE bonds, investment-grade bonds, high-yield bonds, foreign bonds, mortgage-backed bonds and municipal bonds - explained by Beth Stanton.What are the 10 types of bond? ›
- Fixed-rate bonds. Fixed-rate bonds pay consistent interest amounts until maturity. ...
- Floating-rate bonds. Floating-rate bonds do not pay fixed returns each period. ...
- Zero-coupon bonds. ...
- Perpetual bonds. ...
- Inflation-linked bonds. ...
- Convertible Bonds. ...
- Callable Bonds. ...
- Puttable Bonds.
What is the difference between ionic, covalent, and polar bonds? The difference between bond types is simply how they share electrons. Covalent bonds share evenly, polar share unevenly, and ionic bonds don't share at all.What is difference between ionic bond and covalent bond? ›
In ionic bonds, one atom donates an electron to stabilize the other atom. In a covalent bond, the atoms are bound by the sharing of electrons. Atoms that participate in an ionic bond have different electronegativity values from each other.How many types of covalent bonds are there? ›
There are two basic types of covalent bonds: polar and nonpolar.