Introduction to Ionic Bonding and Covalent Bonding

Summary

This educational video explores the fundamental differences between ionic and covalent bonds. Ionic bonding involves electron transfer, typically between metals and non-metals, forming ions that attract each other. Covalent bonds, on the other hand, involve electron sharing, with distinctions between polar and nonpolar based on electronegativity differences. The video uses examples like sodium chloride and hydrogen fluoride to illustrate these concepts, providing a clear guide for understanding chemical bonding.

Takeaways

• 🔬 Ionic bonding involves the transfer of electrons from one atom to another, resulting in the formation of ions.
• 📊 Sodium (Na) and chlorine (Cl) are used as examples to illustrate the formation of ionic bonds, with sodium giving up an electron to chlorine.
• 💡 Metals tend to lose electrons and form positive ions, while non-metals tend to gain electrons and form negative ions.
• ⚛️ The electrostatic force of attraction between oppositely charged ions is what forms the ionic bond.
• 🌐 Covalent bonding involves the sharing of electrons between atoms, as opposed to the transfer seen in ionic bonding.
• 🌀 Hydrogen atoms share their single valence electron to achieve a stable electron configuration, exemplifying covalent bonding.
• 🔍 There are two types of covalent bonds: polar and nonpolar, differentiated by the equality of electron sharing.
• 📊 The bond between two hydrogen atoms is nonpolar because the electrons are shared equally.
• 🌐 In polar covalent bonds, there is an unequal sharing of electrons due to differences in electronegativity between the atoms.
• 📈 Electronegativity is a measure of an atom's ability to attract electrons, with fluorine being the most electronegative element.
• 🔑 To determine if a bond is polar or nonpolar covalent, calculate the electronegativity difference; a difference of 0.5 or more indicates a polar covalent bond.
• 📚 The periodic table is a useful tool for identifying likely ionic compounds (metal and non-metal combinations) and for understanding electron configurations.

Q & A

What is the primary difference between ionic and covalent bonding?

In ionic bonding, electrons are transferred from one element to another, forming ions, while in covalent bonding, electrons are shared between atoms.

Why do metals tend to form positively charged ions?

Metals, like sodium, tend to form positively charged ions because they like to give away their valence electrons to achieve a stable electron configuration.

How does the valence electron count influence the bonding behavior of elements?

Elements with one valence electron, like sodium, tend to lose it to form a +1 ion, while elements with seven valence electrons, like chlorine, tend to gain one electron to form a -1 ion.

What is the significance of the periodic table in predicting the type of bonding?

The periodic table helps in predicting bonding by identifying elements' groups and their valence electrons, which in turn indicates their tendency to form ions or share electrons.

What is the electrostatic force that holds ionic bonds together?

The electrostatic force that holds ionic bonds together is the attraction between oppositely charged ions, such as a positively charged sodium ion and a negatively charged chloride ion.

Why are hydrogen atoms in the first row of the periodic table different from those in the second row?

Hydrogen atoms, being in the first row, aim to have two electrons in their outer energy level to achieve stability, unlike second-row elements which aim for eight electrons to satisfy the octet rule.

What is a covalent bond and how does it differ from an ionic bond?

A covalent bond is formed when two atoms share electrons to achieve a stable electron configuration, unlike ionic bonds which involve the transfer of electrons and the formation of ions.

What determines whether a covalent bond is polar or nonpolar?

A covalent bond is polar if there is an unequal sharing of electrons due to a difference in electronegativity between the atoms, and nonpolar if the electrons are shared equally.

How can you identify a polar covalent bond?

A polar covalent bond can be identified by calculating the difference in electronegativity between the bonded atoms; if the difference is 0.5 or more, the bond is considered polar.

What is electronegativity and how does it affect bond polarity?

Electronegativity is the ability of an atom to attract electrons towards itself. A higher electronegativity difference between bonded atoms results in a polar covalent bond due to the unequal sharing of electrons.

Can you provide an example of a nonpolar covalent bond?

An example of a nonpolar covalent bond is the bond between two hydrogen atoms, where the electrons are shared equally due to the identical electronegativity of both atoms.

How does the presence of hydrogen bonds affect the polarity of a bond?

Hydrogen bonds, such as those formed between hydrogen and oxygen, nitrogen, or fluorine, are inherently polar due to the significant electronegativity difference between hydrogen and the other atom, resulting in an unequal distribution of electron density.

What is the general rule for identifying ionic compounds?

Ionic compounds are generally formed between metals and nonmetals, where metals tend to lose electrons to form positive ions and nonmetals tend to gain electrons to form negative ions.

Outlines

00:00

🔬 Ionic and Covalent Bonding Basics

This paragraph introduces the fundamental concepts of ionic and covalent bonding. Ionic bonding occurs when electrons are transferred from one atom to another, resulting in the formation of ions. An example is the reaction between sodium (a metal from Group 1A) and chlorine (a halogen from Group 7A), where sodium donates its valence electron to chlorine, forming positively charged sodium ions and negatively charged chloride ions. These ions are attracted to each other due to the electrostatic forces between opposite charges, leading to the formation of an ionic bond. The paragraph also contrasts this with covalent bonding, where electrons are shared between atoms, using hydrogen as an example of an element that shares electrons to achieve a stable electron configuration.

05:01

🔍 Distinguishing Polar and Nonpolar Covalent Bonds

The second paragraph delves into the specifics of covalent bonding, explaining the difference between polar and nonpolar covalent bonds. It uses the example of a bond between two hydrogen atoms, which is nonpolar because the electrons are shared equally. In contrast, a bond between hydrogen and fluorine is polar because fluorine, being more electronegative, pulls the electrons towards itself, creating a partial negative charge on fluorine and a partial positive charge on hydrogen. This results in a polar molecule with an unequal distribution of charge, or a dipole. The concept of electronegativity, the ability of an atom to attract electrons, is also introduced, with fluorine being highlighted as having a high electronegativity value.

10:01

📚 Classifying Chemical Bonds with Examples

The final paragraph provides a practical approach to classifying chemical bonds as ionic, polar covalent, or non-polar covalent. It suggests looking for the presence of a metal and a non-metal to identify ionic compounds, such as magnesium oxide (MgO). For covalent bonds, it discusses the importance of electronegativity differences, with a difference of 0.5 or more indicating a polar covalent bond, as illustrated with hydrogen bromide (HBr). The paragraph also touches on special cases like hydrogen bonds and provides a method to determine the polarity of bonds involving carbon, hydrogen, oxygen, and other elements. It concludes with the assertion that understanding these concepts is essential for grasping the nature of chemical bonding.

Keywords

💡Ionic Bonding

Ionic bonding is a type of chemical bond formed by the electrostatic attraction between oppositely charged ions. In the video, it is explained that this occurs when electrons are transferred from one element to another, typically involving a metal giving away electrons to form a cation and a non-metal receiving electrons to form an anion. An example given is the reaction between sodium, which loses an electron to become a positively charged ion, and chlorine, which gains an electron to become a negatively charged ion, resulting in an ionic bond due to the attractive force between the opposite charges.

💡Covalent Bonding

Covalent bonding involves the sharing of electrons between atoms, rather than the transfer as seen in ionic bonding. The video script explains that covalent bonds can be either polar or nonpolar, depending on the electronegativity difference between the atoms involved. A nonpolar covalent bond, such as the one between two hydrogen atoms, involves equal sharing of electrons, while a polar covalent bond, like the one between hydrogen and fluorine, involves unequal sharing due to the higher electronegativity of fluorine.

💡Electron Transfer

Electron transfer is a fundamental process in ionic bonding where one atom donates an electron to another. The video emphasizes that metals, such as sodium, tend to lose electrons easily to achieve a stable electron configuration, while non-metals, like chlorine, tend to gain electrons. This transfer results in the formation of ions, which then attract each other to form ionic bonds.

💡Valence Electrons

Valence electrons are the electrons located in the outermost energy level of an atom and play a crucial role in chemical bonding. The video script uses sodium and chlorine as examples, where sodium, with one valence electron, tends to lose it to form a positive ion, and chlorine, with seven valence electrons, tends to gain one to achieve a stable octet configuration.

💡Electronegativity

Electronegativity is a measure of an atom's ability to attract electrons in a chemical bond. The video explains that this property is key in determining the type of covalent bond formed between atoms. For instance, fluorine, with a high electronegativity value, will pull electrons closer in a bond with hydrogen, resulting in a polar covalent bond.

💡Polar Covalent Bond

A polar covalent bond is a type of covalent bond where the electrons are shared unequally between the atoms due to a significant difference in electronegativity. The video script illustrates this with the bond between hydrogen and fluorine, where fluorine's higher electronegativity causes it to attract the shared electrons more strongly, leading to a partial negative charge on fluorine and a partial positive charge on hydrogen.

💡Nonpolar Covalent Bond

A nonpolar covalent bond occurs when electrons are shared equally between two atoms of the same element, resulting in no separation of charge. The video uses the example of a bond between two hydrogen atoms, where the electronegativity is the same, leading to an equal distribution of electrons and no polarity.

💡Dipole

A dipole refers to a molecule or an object that has a separation of charge, with one side being positive and the other side being negative. The video explains that this occurs in polar covalent bonds, such as the bond between hydrogen and fluorine, where the unequal sharing of electrons results in a polarized object with a distinct positive and negative end.

💡Octet Rule

The octet rule states that atoms tend to form bonds in such a way that they have eight electrons in their valence shell, giving them the same electronic configuration as a noble gas. The video mentions this rule in the context of covalent bonding, where elements like oxygen and fluorine aim to satisfy their octet by sharing, gaining, or losing electrons.

💡Metal and Nonmetal

In the context of the video, metals and nonmetals are differentiated based on their position in the periodic table and their tendency to lose or gain electrons. Metals, found on the left side, tend to lose electrons and form positive ions, while nonmetals, found on the right side, tend to gain electrons and form negative ions. This distinction is crucial for identifying ionic compounds, such as magnesium oxide (MgO), where magnesium is the metal and oxygen is the nonmetal.

💡Hydrogen Bond

Hydrogen bonding is a special type of polar covalent bond that occurs when hydrogen is bonded to highly electronegative atoms like oxygen, nitrogen, or fluorine. The video script mentions that these bonds are always polar due to the significant electronegativity difference, resulting in a strong attraction of electrons towards the more electronegative atom and creating a dipole.

Highlights

The video discusses the fundamental differences between ionic and covalent bonding.

In ionic bonding, electrons are transferred from one element to another, forming ions.

Sodium and chlorine atoms are used as an example to illustrate the formation of ionic bonds.

Sodium, being an alkali metal, tends to lose its valence electron to form a positively charged ion.

Chlorine, a halogen, gains an electron to form a negatively charged anion due to its high reactivity.

The electrostatic force between oppositely charged ions creates an ionic bond.

Covalent bonds involve the sharing of electrons between atoms, as demonstrated with hydrogen atoms.

Hydrogen atoms share electrons to achieve a stable electron configuration with two electrons in their outer shell.

Covalent bonds are categorized into polar and nonpolar based on the sharing of electrons.

A nonpolar covalent bond, like the one between two hydrogen atoms, involves equal sharing of electrons.

Polar covalent bonds result from unequal electron sharing due to differences in electronegativity between atoms.

Electronegativity is the measure of an atom's ability to attract electrons, with fluorine being the most electronegative element.

The video provides a method to determine the polarity of covalent bonds using electronegativity differences.

An electronegativity difference of 0.5 or more indicates a polar covalent bond.

Examples of different types of bonds are given, including magnesium oxide (ionic), chlorine atoms (nonpolar covalent), and sodium fluoride (ionic).

Hydrogen bromide (HBr) is identified as a polar covalent bond due to a significant electronegativity difference.

Iodine monobromide is classified as a relatively nonpolar covalent bond based on a smaller electronegativity difference.

Carbon-hydrogen bonds are memorably nonpolar due to a small electronegativity difference.

Hydrogen bonds, such as the OH bond, are inherently polar due to the high electronegativity of oxygen.

The video concludes with a summary of the key differences between ionic and covalent bonds.

Transcripts

in this video we're going to discuss the

difference between ionic and covalent

bonding

in ionic bonding

electrons are transferred from one

element to another and typically ionic

bonds contain ions

in a covalent bond electrons are shared

but let's go over ionic bonding first

let's consider the reaction between an

atom of sodium and an atom of chlorine

sodium

as an atom has one valence electron

if you look where it is in the periodic

table it's in the first column it's in

group 1a

of the periodic table and elements in

that group all contain one valence

electron

a valence electron is simply the

electrons in the last

or outermost energy level

chlorine which is a halogen

contains

seven valence electrons it's in group 7a

of the periodic table

the halogens are very reactive

non-metals

and the alkali metals where sodium is

found

are very reactive metals metals like to

give away electrons and so they form

positively charged ions

non-metals they like to receive

electrons

and so they form negatively charged

anions

so sodium

is going to give chlorine

one of its electron or valence electron

since it only has one

so as sodium loses that one valence

electron

it's going to acquire a positive charge

and as chlorine gains

that electron

it requires a negative charge

now going back to physics

if you have two like charges next to

each other what's going to happen

like charges repel

they're going to feel an electric force

that repels them or pushes them away

from each other

but what's going to happen if you have a

positive

and a negative charge

next to each other

these two are attracted to each other

they feel a force of attraction that

pulls them together

and so that's what's happening between

the sodium ion and the chloride ion

the sodium ion which now has a net

positive charge is attracted to the

chloride ion which has a negative charge

and so these two they feel a force of

attraction

and that force of attraction that

electrostatic force

it binds them together and so that

creates the ionic bond

so keep this in mind

within ionic bonds you have a transfer

of electrons

and the bonds that hold them

are as a result of the electrostatic

forces between

opposite charges keep in mind opposite

charges attract each other

so now let's move on into covalent

bonding

let's look at hydrogen

a hydrogen atom has one valence electron

and

it's in the first row of the periodic

table

elements in the first row

they want to have a total of two

electrons in their outer energy level

the second row elements they want to

have eight electrons

so elements like oxygen fluorine they

want to satisfy their octet they want to

have eight electrons but hydrogen and

helium they can only have two electrons

in their first shell

so each of these hydrogens they need one

more electron to fill that first shell

with a total of two electrons

and both of these elements are the same

so what they're going to do is they're

going to share

their electrons

and so these two they're going to form a

bond

so when you see a bond this bond

represents the sharing of two

electrons and so this is a covalent bond

anytime you have sharing of electrons

it's a covalent bond

now there's two types of covalent bonds

you need to be familiar with

polar covalent bonds

and nonpolar covalent bonds

the bond between two hydrogen atoms is

considered to be a nonpolar covalent

bond the reason why it's nonpolar is

because the electrons are shared equally

between those two hydrogen atoms

now if you look at the bond between

hydrogen and fluorine

the elements are different

fluorine is much more electronegative

than hydrogen

because fluorine is electronegative

it's going to pull the electrons toward

itself

now granted

the electrons are still being shared but

they're being shared unequally

and whenever you have an unequal sharing

of electrons

you have a polar

covalent bond

as opposed to

a nonpolar

covalent bond

so because fluorine is more

electronegative

as it pulls the electrons toward itself

fluorine is going to acquire a partial

negative charge and hydrogen is going to

be partially positive

and whenever you have an object where

one side is positive and the other side

is negative

you have a dipole you have a polarized

object

and this is what it means to be polar

you have

an unequal distribution of

charge one side is positive one side is

negative so the electrons they're not

distributed evenly

in that molecule

the electrons spend more time closer to

fluorine because it's more

electronegative

electronegativity is the ability of an

atom

to

attract an electron toward itself and

fluorine it does a good job in doing

that

so now you know what a polar covalent

bond is

it's a bond where you have unequal

strand of electrons and a non-polar

covalent bond is a bond where you have

equal sharing of electrons

now let's go over some practice problems

i want you to classify

the following bonds

as being ionic

polar covalent or non-polar covalent

so let's start with the first one

mgo

magnesium oxide

is it ionic polar covalent or non-polar

covalent

the first thing i would look for is to

see if it's ionic

typically

an ionic compound consists of a metal

and a non-metal that's how you can

easily identify it

magnesium is a metal

metals exist on the left side of the

periodic table

nonmetals exist on the right side the

nonmetals are on the upper right side

the metals are on the lower left side

so magnesium

is a metal

and oxygen which is on the upper right

side of the periodic table that's a

nominal

so this is going to be ionic

magnesium

forms a plus two

charge as an ion

it has two valence electrons so in this

bond

it's going to give away two electrons to

oxygen

oxygen

which is a calcagen

magnesium is an alkaline earth metal

but oxygen

it has six valence electrons it needs

two more to get to eight so once it

acquires those two electrons it's going

to have a negative charge as you can see

this compound is composed of ions

now what about two chlorine atoms

chlorine is a nominal whenever you have

two nonmetals with the same type of

element

it's always going to be a nonpolar

covalent

the electrons are shared equally

because we have the same type of atom

now what about sodium fluoride

sodium is on the left side of the

periodic table so it's a metal

and fluorine is a halogen on the right

side so that's a non-metal so sodium

fluoride contains ionic bonding

now what about hbr

is it polar covalent

or nonpolar covalent

now the elements are different so that

could be an indication that it might be

polar covalent but you need to run a

test

you need to calculate the difference in

electronegativity

if the electronegativity difference

is equal to or greater than 0.5

most textbooks they use this number

if it's 0.5 or more then the bond is

considered to be polar covalent

if it's less than 0.5 if it's 0.4 or

less

then it's considered to be non-polar

covalent

so if you need the electronegativity

values you can go to google images

and type in

electronegativity table and you'll see

some tables come up

now i've seen different tables with

different values they don't very much

but sometimes they do vary

so if you're doing a homework problem

use whatever table your book gives you

in the table that i use

hydrogen

has an electronegativity value of 2.1

bromine it's about 2.8

and so the en difference

is 0.7

therefore this is going to be

polar

covalent i'm going to write pc for polar

covalent

now what about

iodine

monobromide

what is the difference in

electronegativity

iodine has

an electronegativity value of 2.5 and

for bromine 2.8

so the en difference

is about 0.3

which means that it's relatively

non-polar covalent so i'm going to write

unseen again make sure you use the table

that your book provides because if the

values are slightly different

the result might be different

but the idea is that you want to find

an ian difference of 0.5 or more to see

if it's polar or not

so let's try some more examples

determine if the following bonds

is polar covalent

non-polar covalent or ionic

so let's look at carbon and hydrogen

has an electronegativity value of 2.5

and for hydrogen is 2.1

so the en difference is 0.4

for this one i would commit this memory

anytime you see carbon hydrogen it's

going to be nonpolar

this is a very common example that

you'll see within chemistry and even

organic chemistry

now what about the oh bond

whenever hydrogen is bonded to oxygen

nitrogen or fluorine you have a special

case of bonding known as hydrogen bonds

whenever you have hydrogen bonds it's

going to be polar by the way

oxygen has an electronegativity value of

3.5

so 3.5 minus 2.1 the difference is huge

so 1.4 this bond is very polar

so this is polar covalent

this is non-polar covalent

now if the two atoms are the same and

they're both not metals

it's going to be non-polar covalent you

don't really need to do the calculation

fluorine has an electronegativity value

of 4.0 4 minus 4 is 0 which is less than

0.5

now calcium sulfide

for this you really don't need the

electronegativity values you just need

to know that calcium is a metal

and sulfur is a nominal

and then so you could say it's ionic

if you have one element all the way to

the left side of the periodic table and

another all the way to the right side

it's going to be ionic

so that is it for this video now you

understand the difference between ionic

and covalent bonding so thanks for

watching and have a great day