bonding, structure and the properties of matter

what are the three types of strong chemical bonds

<ul><li>ionic</li><li>covelant</li><li>metallic</li></ul>

what is an ion

a charged particle - can be negative or positive<br>can be single atom or multiple<br>are formed when atoms gain or lose electrons to have a full outer shell

how many electrons do group one elements have to lose to have a full outer shell<br>does this require a lot of energy

have to lose 1 electron<br>doesnt require much energy

&nbsp; what is the ionic equation of sodium

Na --&gt; Na⁺&nbsp;+ e^-&nbsp;<br><br>written after arrow because sodium loses electron to be stable

what is the ionic equation of chlorine

Cl + e^-&nbsp;---&gt; Cl^-&nbsp;<br>written after arrow as it has to gain an electron to be stable<br>gaining an electron makes it a negative ion

when an atom is becoming a positive ion and is gaining an electron on which side of the ionic reaction do we write this

on the right of the equation (element only on left)

when an atom is becoming a negative ion and is losing an electron on which side of the ionic reaction do we write this

we put the electron on the left to show how it's combining with the atom to become stable

what is the ionic equation of magnesium<br>what is the charge of magnesium

magnesium has a 2+ charge as it loses 2 electrons<br>Mg ---&gt; Mg²⁺&nbsp;+ 2e^-&nbsp;<br>

what is the ionic equation for oxygen

O +2e^-&nbsp;---&gt; O^2-&nbsp;

ionic bonding occurs in what compound

ionic bonding occurs in compounds from metals combined with non metals

in ionic bonding, when a metal atoms reacts with a non metal atom, what happens to the electrons

the electrons are transferred , metal atoms lose electrons to become positively charged ions and the non metals gain electrons to become negatively charged ions&nbsp;

in what type of diagram do we show ionic bonding

dot and cross diagrams

how would you show the ionic bonding of sodium and chlorine, including the charges

"<img src=""paste-afae3e00607d774ab24e4ba09bc93df646b7b82c.jpg"" width=""570""><br>the electron from sodium transfers to the outer shell of chlorine<br>this allows sodium and chlorine to both have a full outer shell<br>as a result, sodium has a positive charge and chlorine has a negative charge<br>MUST PUT BIG SQUARE BRACKETS AROUND THEM AND THEIR CHARGE IN THE TOP RIGHT CORNER"

aside from ionic bodnign being between metals and non metals, what else must the the atoms be

the atoms must be of opposite charges so they are attracted to each other by electrostatic forces to form an ionic compound

what do we get as a result of ionic bonding

an ionic compound / bond

how strong is an ionic bond?

really strong

draw the dot and cross diagram for the formation of magnesium chloride

"<img src=""paste-13463099ac3d8be2af44cc53143a7496cc9f48d9.jpg"" width=""613""><br>"

what is an ionic compound

a giant structure of ions&nbsp;

how are ionic compounds held together

held together by strong electrostatic forces&nbsp; between oppositely charged ions

what is the structure of an ionic compound

"3D structure<br>these electrostatic forces happen in all directions in the lattice&nbsp;<br>REGULAR LATTICE STRUCTURE<br><br><img src=""paste-03a761879b81fcc6d9fa5849e03955dfdc874602.jpg"">"

asside from a regular lattice structure with oppositely charged ions stuck together, how else can we represent ionic compounds

"using a ball and stick diagram&nbsp;<br><img src=""paste-325df2a54a3c99c9b4edccd344dd00072e18f0cd.jpg"">"

for the properties of an ionic compound, do they have a high or low melting and boiling points? why?<br>

ionic compounds have high melting and boiling points<br>the melting and boiling points are determined by the strength of the bonds holding that substance together, in ionic compounds there are lots of strong ionic bonds which would require lots of energy to break them all - which will only be available at high temperatures

for the properties of an ionic compound, can ionic compounds conduct electricity? explain why/why not?

yes but only when they are melted or dissolved in water<br>substances can only conduct electricity where there are any charged particles that can move (can either be ions or electrons)<br>when ions are in their solid form, everything is fixed so they conduct any electricity BUT when they're melted or dissolved in water, the ions are free to move about - this movement of charged particles allows them to condct electricity

what is the charge + symbol of hydroxide ions

OH^-

what is the charge+symbol of a sulfate ion

SO₄^2-

what is the formula of calcium hydroxide

"Ca(OH)₂&nbsp;<br><img src=""paste-f35ede0ff154419c7120343e46e915681c3b9beb.jpg""><br>have to put bracket around )H to show we want 2 whole OH ions and not 2 hydrogens"

what is the formula for aluminium sulfate

"Al₂(SO₄)_3<br><br><img src=""paste-bdb0f795dec232dc730ee09575ac3dc81aa9bf12.jpg"">"

what is the charge/formula for a nitrate ion

NO₃^-

what is the charge/formula for the carbonate ion

CO₃^2-

what is the charge/ formula for the ammonium ion

NH₄⁺

what is the formula for the ionic compound potassium chloride

KCl

what is the chemical formula for calcium sulfate

CaSO₄

what does the molecular formula of a substance show

the molecular formula of a substance shows the actual number of atoms of each element present in a compound or molecule

what is the empirical formula of a substance

the simplest, whole number ratio of atoms of each element in a compound - doesnt tell you exactly how many atoms there are, just the ratio of the atoms of each element

what is the empirical and molecular formula of glucose

molecular :C₆H₁₂O₆&nbsp;<br>empirical: CH₂O<br>empirical formula just sows that the ratio of carbon:hydrogen is 1:2:1 so for every carbon atoms there's 2 hydrogen atoms and 1 oxygen atom

"what is the emprical formula of ethana - C₂H₆<br><span style=""font-size: 16.6667px;""><br></span>"

"<img src=""paste-7edef069b1facf5e55cf9f6c8ecc5172dd15bf57.jpg"">"

an unknown compound has an empirical formula of CH₃&nbsp;and an Mr of 30<br>find the molecular formula of the compound

"C₂H_6<br><img src=""paste-79ae6f9383f3c744c069f20b0300ac2155f8382c.jpg"">_<br>"

"<div><span style=""font-weight: 600 !important;"">An unknown compound has an&nbsp;empirical formula of CH</span>₂<span style=""font-weight: 600 !important;"">O, and an&nbsp;Mr of 180.</span></div><div><span style=""font-weight: 600 !important;"">Find the&nbsp;molecular formula&nbsp;of the compound.</span></div>"

C₆H₁₂O₆

<div>'A compound is found to contain&nbsp;<strong>50.05% sulfur</strong>&nbsp;and&nbsp;<strong>49.95% oxygen</strong>&nbsp;by weight. What is the&nbsp;<strong>empirical formula</strong>&nbsp;for this compound?'</div>

"SO₂&nbsp;<br><img src=""paste-8124a414fec905a3e5c9311ad65d00b4d38f8302.jpg"">"

"<img src=""paste-d47e8d9c29a6f7a60681b43117f945907ef73ad6.jpg"">"

"<img src=""paste-2329909cdfde7c8cec9098d424f041c6afbe0352.jpg"">"

"<img src=""paste-1d79d851a64ed4f2c4d56fa2cc7b0e70747a857d.jpg"">"

"<img src=""paste-fc93302fd39ed214b3bf0dbbb2ba00a983e88e3e.jpg"">"

"<img src=""paste-8d44fa7ea37b2fb0337433c4ace7c6a68a028ec4.jpg"">"

"<img src=""paste-e0efcf7c63b4dbd7d5bc96ad8897f819ac171edd.jpg"">"

how do atoms form covalent bonds

by sharing electrons

how do we draw covalent bonds

draw a dot and cross diagram

apart from a dot and cross diagram , how else can we draw covalent bonds

using a displayed formula&nbsp;

why would we use a displayed formula instead of a dot and cross diagram

they are easier to draw bigger and more complex atoms

what is a disasvnatage of a displayed formula

they dont show you anything about the 3D shape of the molecule - use a 3d model instead

what types of substances can covalent bonds make

"<ul><li>simple molecular substances e.g., chlorine, ammonia (atoms joined by strong covalent bonds but between the <span style=""background-color: rgb(255, 0, 127);"">individual molecules there are weak intermolecular forces which are easily broken</span>)</li><li>water, methane</li><li>can make larger structures like polymers (long chains of monomers) and giant covalent structures (silicon dioxide, diamond, graphite)</li></ul>"

do covalent bonds form between metallic or non metalic atoms

non metallic

why do many simple molecules have low melting and boiling points

<ul><li>the covalent bonds between atoms are very strong</li><li>however, the forces of attraction between seperate molecules are weak and so simple molecules are easily seperated from each other</li><li>this is why many simple molecules have low melting and boiling points - the intermolecular forces (force between molecules) only require a small amount of energy to break, which means they'll break at low temperatures</li></ul>

non metals bond covalently to form

giant covalent structures

examples of giant covalent structures

<ul><li>diamond</li><li>silicon dioxide</li><li>graphite</li></ul>

what is needed to break the covalent bonds in simple molecular subtsances

lots of energy

how can we melt/ boil simple molecular substances e.g., chlorine

<ul><li>we dont need to break the covalent bonds</li><li>instead we need to break the weak forces that exist between the molecules (intermolecular forces)</li><li>therefore we only need low temperatures to melt or boil simple molecular subtsances</li></ul>

what temperature does chlorine boil at

-34 degrees celcius

even thought the intermolecular forces are weak, the more a molecule has, does the attraction get stronger or weaker

the sttraction gets stronger

why does the boiling point increase going down the group of halogens

the molecules get larger (the intermolecular forces get stronger)

why dont simple molecular substances conduct electricity

there are no free electrons and the molecules themselves dont have electric charge

what are giant covalent structures made up of

<ul><li>huge numbers of non metal atoms - all bonded by covalent bonds</li><li>arranged into regular repeating lattices</li></ul>

why do giant covelant structures have high melting and boiling points

<ul><li>you have to break all the strong covalent bonds to melt them</li></ul>

why is the exception for giant covalent structures not conducting electricity

graphite

what is silicon dioxide made of

silicon and oxygen atoms in&nbsp; a ratio of 1:2<br>aka silica<br>main component of sand

in what stae do most simple molecular substances exist in

gaseous

what state is bromine at room temp

liquid

what are the&nbsp; allotropes of carbon

diamond and graphite<br>graphene and fullerene

what is an allotrope

different strucural forms of the same element in the same physical state

desrcibe the structure of a diamond

<ul><li>regular lattice covalent structure</li><li>each carbon is covalently bonded to 4 other carbon atoms&nbsp;</li><li>forms a regular 3D pattern</li></ul>

properties of diamond

strong covalent bond<br>diaomond is strong - high melting point<br>doesnt conduct electricity as it has no free electrons or ions that can mocve around

in graphite, each carbon atom is bonded to how many other carbon atoms

each carbon atom is bonded to 3 other carbon atoms

in graphite, how are the atoms arranged

atoms are arranged into hexagons which together fom large flat sheets which are then arranged on top of one another to form lots of layers<br><br>these individual layers are held together weakly s there are no covalent bonds between them - means they are free to slide over one another<br>=graphite is soft compared to diamond

why does graphite have a high melting point

the individual layers are still held strongly together with covalent bonds

why can graphite conduct electricity

<ul><li>since it only has 3 carbon bonds, each carbon atos has 1 spare electron</li><li>isntead this electron becomes delocalised which means its free to move around</li><li>all these free electrons allow the graphite to conduct electricity and heat</li></ul>

what is a single layer of graphte called

graphene

what can scientists use the individuald graphenes for

to make other structures like speheres and tubes, call them fullerenes

explain why graphite is a lot softer than diamond

<ul><li>this is because the 2D layers of graphite stack on top of each other with only weak intermolecular forces holding them together</li><li>this means the layers can slide over each other, making graphite easier to break</li></ul>

what are the allotropes of carbon

graphene and fullerenes

what is an allotropes&nbsp;

different structural forms of the same element in the same physical state

what are the layers in graphite called

graphene

explain the structure of a graphene

3 carbon bonds - very strong<br>multiple repeating hexagons

where can we get graphene

from the ground in the form of graphite

what can scientists do with graphene

make shapes out of them e.g, tubes, pentagons/ heptagons - makes them curve into speheres<br>these tiny tubes and spheres are <b>fullerenes</b>

main uses of fullerenes

<ul><li>scientists can form these spheres around other molecules e.g., drugs, so it acts like a cage and can be used to deliver the drug to certain areas of the body</li></ul><ul><li>fullerenes have a large SA: V ratio - can be used to make industrial catalysts (used to speed up rate of reaction)</li></ul><ul><li>tubes (nanotubes - because theyre so tiny) can be used in nanotechnology and in electricity because of their ability to conduct electricity + can also be used to strenghten other materials like tennis racket frames - because of the very high length: diameter ratio (long and thin) which allows them to add strength to a material without much weight</li></ul>

what was one of the first fullerenes made

"<img alt=""The structure of Buckminsterfullerene, downloadable IB Chemistry revision notes"" src=""4.1.11-The-structure-of-Buckminsterfullerene-1.png""><br><br>sphere<br>buckminsterfullerene&nbsp;"

whats the structure of the buckminster fullerene

<ul><li>hollow sphere</li><li>made of 60 carbon atoms</li><li>C60</li></ul>

what do we call the technology that uses tiny fullerene structures

nano technology

what industries is nanotechnology used in&nbsp; (/products)

<ul><li>medicine</li><li>batteries</li><li>food</li><li>fashion</li></ul>

are fullerenes hollow?

yes

what shapes are fullerenes

spheres or tubes

in what atoms does metallic bonding occur

metal atoms

metals bond to non metals through what bonding

ionic bonding

non metals to non metals bond with what bonding

covalent bonding

what is the general structure of a solid metal

<ul><li>giant structure of atoms that are arranged in a regular pattern</li></ul>

why do metals consist of positive ions

<ul><li>all atoms have electrons in their outermost shell</li><li>when they're all together in a metal, they give up these outer shell electrons and share them with all the other atoms in the metal</li><li>this means all the atoms will because positive ions because theyve lost negative electrons</li></ul>

what holds everything together in regular structure in a metal

<ul><li>after losing their outer electrons to share with the other metals</li><li>the electrons are free to move about, we call them delocalised electrons</li><li>so there will now be lots of strong electrostatic attraction between the positive ions and the negative electrons and its this force of attracition that holds everything together ina&nbsp; regular structure</li><li>metallic bonding</li></ul><br>

do metallic structure have low or high melting and boiling points

high melting and boiling points as they have strong electrostatic attraction to overcome (requires lots of energy)

why are metals good conductors of electricity and heat

<ul><li>the delocalised electrons can carry electrical current and thermal energy throughout the structure</li></ul>

are metals malleable

<ul><li>can easily be bent or hammered into shapes e.g., thin sheets</li></ul>

why are metals malleable

<ul><li>since they have a regular structure</li><li>it means the different layers can slide over one another</li></ul>

what do we make if we want harder metals that dont bend so easily

make alloys

what do alloys contain

2 or more different elements