C2 - Bonding, Structures and Properties of Matter Flashcards
What are ions?
Charged particles that can be single atoms or groups of atoms.
How are ions formed?
When atoms lose or gain electrons to achieve a stable electronic structure.
What is a stable electronic structure?
Having a full outer shell of electrons, similar to noble gases.
Which group of the periodic table contains noble gases?
Group 0.
What happens when metals form ions?
They lose electrons from their outer shell to form positive ions.
What happens when non-metals form ions?
They gain electrons into their outer shell to form negative ions.
What does the charge on an ion represent?
The number of electrons lost or gained.
If 2 electrons are lost, what is the charge of the ion?
2+.
If 3 electrons are gained, what is the charge of the ion?
3-.
Which groups in the periodic table are most likely to form ions?
Groups 1, 2, 6, and 7.
What type of elements are in Groups 1 and 2?
Metals that lose electrons to form positive ions (cations).
What type of elements are in Groups 6 and 7?
Non-metals that gain electrons to form negative ions (anions).
How can you determine the charge of ions formed by elements in the same group?
They have the same number of outer electrons and thus lose or gain the same number.
What charge do Group 1 elements typically form?
1+ ions.
What charge do Group 2 elements typically form?
2+ ions.
What charge do Group 6 elements typically form?
2- ions.
What charge do Group 7 elements typically form?
1- ions.
What is the electronic structure of a sodium ion (Na+)?
It has the same electronic structure as neon.
What is the electronic structure of a magnesium ion (Mg2+)?
It has the same electronic structure as neon.
What is the electronic structure of a chloride ion (Cl-)?
It has the same electronic structure as argon.
What is the electronic structure of an oxide ion (O2-)?
It has the same electronic structure as neon.
Fill in the blank: Ions are charged particles that can be single atoms or _______.
groups of atoms.
True or False: All elements form ions with different charges.
False.
What is ionic bonding?
The transfer of electrons between a metal and a non-metal, resulting in the formation of oppositely charged ions that are attracted to each other.
Ionic bonds are characterized by the electrostatic forces between positively and negatively charged ions.
What happens to a metal atom during ionic bonding?
It loses electrons to form a positively charged ion.
This process is crucial for forming ionic compounds.
What happens to a non-metal atom during ionic bonding?
It gains electrons to form a negatively charged ion.
Non-metals typically have higher electronegativities, allowing them to attract electrons.
What is a dot and cross diagram?
A diagram that shows the arrangement of electrons in an atom or ion, using dots and crosses to represent electrons from different atoms.
These diagrams help visualize the transfer of electrons during ionic bonding.
What is the ionic bond in sodium chloride (NaCl)?
The sodium atom loses an outer electron to become Na+, and the chlorine atom gains that electron to become Cl-.
This transfer of electrons results in the formation of the ionic compound sodium chloride.
What are the electron configurations of sodium and chloride ions?
Sodium ion: 2, 8; Chloride ion: 2, 8, 8.
The electron configurations show that both ions achieve a stable electron arrangement.
What occurs in the formation of magnesium oxide (MgO)?
Magnesium gives up two outer electrons to become Mg2+, and oxygen gains those electrons to become O2-.
This results in the ionic compound magnesium oxide.
What is the process of forming magnesium chloride (MgCl2)?
Magnesium loses two outer electrons to become Mg2+, and two chlorine atoms each gain one electron to become two Cl- ions.
This demonstrates the stoichiometry involved in ionic bonding.
What happens when sodium oxide (Na2O) is formed?
Two sodium atoms each lose one electron to become Na+, and the oxygen atom gains two electrons to become O2-.
The resulting ionic compound is sodium oxide.
True or False: Dot and cross diagrams show the structure of ionic compounds.
False.
Dot and cross diagrams illustrate electron transfer but do not depict the structure or arrangement of ions in the compound.
Fill in the blank: The attraction between oppositely charged ions is called an _______.
ionic bond.
Ionic bonds are fundamental in the formation of ionic compounds.
What is the significance of group number in determining electron gain or loss?
It indicates how many electrons an atom will gain or lose during bonding.
The group number helps predict the charge of ions formed from elements.
What is the structure of ionic compounds called?
Giant ionic lattice
Ionic compounds have a regular lattice structure due to the electrostatic attraction between oppositely charged ions.
What type of bonding occurs in ionic compounds?
Ionic bonding
Ionic bonding is the strong attraction between oppositely charged ions in all directions.
List two properties of ionic compounds.
- High melting points
- High boiling points
These properties are due to the many strong bonds between the ions.
When can ionic compounds conduct electricity?
When they are melted or dissolved in water
In solid form, ions are held in place and cannot carry electric charge.
What happens to ionic compounds when they dissolve in water?
The ions separate and are free to move
This allows them to carry electric charge in solution.
How can you determine the empirical formula of an ionic compound from a diagram?
Count the number of atoms of each element
Use dot and cross diagrams or 3D diagrams to identify ions.
What charge does a potassium ion form?
1+ charge
Potassium is in Group 1 of the periodic table.
What charge does an oxide ion form?
2- charge
Oxygen is in Group 6 of the periodic table.
Fill in the blank: The empirical formula for the ionic compound formed by potassium and oxide ions is _______.
K2O
Two potassium ions are needed to balance the 2- charge of one oxide ion.
True or False: Ionic compounds have gaps between their ions.
False
In reality, there are no gaps between the ions in the lattice structure.
What type of model can represent the structure of an ionic crystal?
Ball and stick model
This model shows the relative sizes of the ions and the regular pattern of the ionic crystal.
What is covalent bonding?
Covalent bonding is where atoms share electrons with each other to achieve full outer shells.
How do non-metal atoms bond together?
Non-metal atoms bond together by sharing pairs of electrons to form covalent bonds.
What attracts the positively charged nuclei of bonded atoms to the shared pair of electrons?
Electrostatic forces.
What is the significance of a full outer shell in atoms?
Having a full outer shell gives atoms the electronic structure of a noble gas, which is very stable.
What is the general rule for how many covalent bonds an atom makes?
Each atom involved generally makes enough covalent bonds to fill up its outer shell.
What types of compounds exhibit covalent bonding?
Covalent bonding occurs in compounds of non-metals and in non-metal elements.
What are dot and cross diagrams used for?
Dot and cross diagrams are used to show the bonding in covalent compounds.
What do dot and cross diagrams not show?
They do not show the relative sizes of the atoms or how the atoms are arranged in space.
How many outer electrons does nitrogen have?
Nitrogen has five outer electrons.
What does a displayed formula represent?
A displayed formula shows the covalent bonds as single lines between atoms.
What does a 3D model of a molecule show?
A 3D model shows the atoms, the covalent bonds, and their arrangement in space.
What is a molecular formula?
A molecular formula shows how many atoms of each element are in a molecule.
Fill in the blank: Each single covalent bond provides one extra _______ for each atom.
shared electron.
True or False: 3D models can become confusing for large molecules.
True.
How can you find the molecular formula of a simple molecular compound?
By counting up how many atoms of each element there are in a diagram.
What is the molecular formula for ethane, based on its diagram?
C2H6.
What are simple molecular substances made up of?
Molecules containing a few atoms joined together by covalent bonds
What is the chemical formula for chlorine?
Cl2
How many electrons does a hydrogen atom need to complete its outer shell?
1
What type of bond do two chlorine atoms form?
Single covalent bond
What is the chemical formula for oxygen gas?
O2
How many pairs of electrons do two oxygen atoms share?
2 pairs
What type of bond is formed between two nitrogen atoms?
Triple bond
What is the chemical formula for methane?
CH4
How many covalent bonds can carbon form?
4
What is the chemical formula for water?
H2O
How many single covalent bonds are formed in a water molecule?
2
What is the chemical formula for hydrogen chloride?
HCl
What type of forces are present between simple molecular substances?
Weak intermolecular forces
What holds the atoms within the molecules together?
Strong covalent bonds
What is needed to melt or boil a simple molecular compound?
Breaking weak intermolecular forces
What state are most molecular substances in at room temperature?
Gases or liquids
What happens to the melting and boiling points as molecular size increases?
They increase
Do molecular compounds conduct electricity?
No
Fill in the blank: Hydrogen atoms need ______ to complete their outer shell.
1 electron
Fill in the blank: In oxygen gas, two oxygen atoms share ______ pairs of electrons.
2
True or False: The forces of attraction between molecules in simple molecular substances are very strong.
False
What are polymers?
Long chains of repeating units
Polymers are made up of small units linked together to form a long molecule with repeating sections.
How are the atoms in a polymer joined?
By strong covalent bonds
All atoms in a polymer are connected through strong covalent bonds.
What is a repeating unit in a polymer?
The shortest section that repeats
The repeating unit represents the structure that is repeated throughout the polymer.
What is the molecular formula notation for a polymer?
(C,Ha)n
The notation indicates the molecular formula of the repeating unit in brackets, followed by ‘n’ to denote repetition.
What do the intermolecular forces between polymer molecules compare to those of simple covalent molecules?
Larger than simple covalent molecules
This results in more energy being needed to break these forces, making most polymers solid at room temperature.
Do polymers generally have higher or lower boiling points compared to ionic or giant molecular compounds?
Lower boiling points
Polymers have weaker intermolecular forces than ionic or covalent bonds.
What are giant covalent structures?
Macromolecules with strong covalent bonds
In these structures, all atoms are bonded together by strong covalent bonds.
What are the melting and boiling points of giant covalent structures?
Very high
A lot of energy is required to break the covalent bonds in these structures.
Do giant covalent structures conduct electricity?
No, they do not conduct electricity
They do not contain charged particles, except for some exceptions like graphite.
What are the main examples of giant covalent structures?
- Diamond
- Graphite
- Silicon dioxide (silica)
These structures are primarily composed of carbon atoms or silicon and oxygen.
How many covalent bonds does each carbon atom form in diamond?
Four covalent bonds
This results in a very rigid giant covalent structure.
How many covalent bonds does each carbon atom form in graphite?
Three covalent bonds
Graphite forms layers of hexagons, with each carbon atom having one delocalised (free) electron.
What is silicon dioxide commonly known as?
Silica
Silica is what sand is made of, and each grain of sand is a giant structure of silicon and oxygen.
What is the structure of diamond?
Diamond has a giant covalent structure made up of carbon atoms that each form four covalent bonds.
Why is diamond very hard?
The strong covalent bonds in diamond take a lot of energy to break.
Does diamond conduct electricity?
No, diamond does not conduct electricity because it has no free electrons or ions.
What is the arrangement of carbon atoms in graphite?
In graphite, each carbon atom forms three covalent bonds, creating sheets of carbon atoms arranged in hexagons.
What property of graphite allows it to be used as a lubricant?
Graphite is soft and slippery because the layers are held together weakly and can move over each other.
What type of melting point does graphite have?
Graphite has a high melting point due to the strong covalent bonds in the layers.
What is graphene?
Graphene is a sheet of carbon atoms joined together in hexagons, just one atom thick.
What are the properties of graphene?
Graphene is very strong, incredibly light, and contains delocalised electrons that allow it to conduct electricity.
What are fullerenes?
Fullerenes are molecules of carbon shaped like closed tubes or hollow balls.
What is Buckminsterfullerene?
Buckminsterfullerene is the first fullerene to be discovered, with the molecular formula C60, forming a hollow sphere.
How can fullerenes be used in drug delivery?
Fullerenes can ‘cage’ other molecules, trapping them inside for delivery into the body.
What industrial application do fullerenes have due to their structure?
Fullerenes have a huge surface area, making them great industrial catalysts.
What are nanotubes?
Nanotubes are tiny carbon cylinders formed from fullerenes.
What properties do nanotubes possess?
Nanotubes can conduct electricity and thermal energy, and have high tensile strength.
What is nanotechnology?
Nanotechnology is technology that uses very small particles, such as nanotubes.
Fill in the blank: Graphene is a _______ substance.
[two-dimensional]
What is the structure of diamond?
Diamond has a giant covalent structure made up of carbon atoms that each form four covalent bonds.
Why is diamond very hard?
The strong covalent bonds in diamond take a lot of energy to break.
Does diamond conduct electricity?
No, diamond does not conduct electricity because it has no free electrons or ions.
What is the arrangement of carbon atoms in graphite?
In graphite, each carbon atom forms three covalent bonds, creating sheets of carbon atoms arranged in hexagons.
What property of graphite allows it to be used as a lubricant?
Graphite is soft and slippery because the layers are held together weakly and can move over each other.
What type of melting point does graphite have?
Graphite has a high melting point due to the strong covalent bonds in the layers.
What is graphene?
Graphene is a sheet of carbon atoms joined together in hexagons, just one atom thick.
What are the properties of graphene?
Graphene is very strong, incredibly light, and contains delocalised electrons that allow it to conduct electricity.
What are fullerenes?
Fullerenes are molecules of carbon shaped like closed tubes or hollow balls.
What is Buckminsterfullerene?
Buckminsterfullerene is the first fullerene to be discovered, with the molecular formula C60, forming a hollow sphere.
How can fullerenes be used in drug delivery?
Fullerenes can ‘cage’ other molecules, trapping them inside for delivery into the body.
What industrial application do fullerenes have due to their structure?
Fullerenes have a huge surface area, making them great industrial catalysts.
What are nanotubes?
Nanotubes are tiny carbon cylinders formed from fullerenes.
What properties do nanotubes possess?
Nanotubes can conduct electricity and thermal energy, and have high tensile strength.
What is nanotechnology?
Nanotechnology is technology that uses very small particles, such as nanotubes.
Fill in the blank: Graphene is a _______ substance.
[two-dimensional]
What is metallic bonding?
Involves delocalised electrons and strong electrostatic forces of attraction between positive metal ions and shared negative electrons.
Metallic bonding is characterized by the ability of electrons to move freely, which contributes to various properties of metals.
What are the properties of metals due to delocalised electrons?
Metals exhibit high melting and boiling points, good electrical and thermal conductivity, and malleability.
The delocalised electrons in metallic bonds are responsible for these properties.
Why are most metals solid at room temperature?
Most metals have very high melting and boiling points due to strong electrostatic forces between metal atoms and delocalised electrons.
These strong forces require a lot of energy to break.
What is the significance of delocalised electrons in metals?
They carry electrical charge and thermal energy through the metal structure, making metals good conductors of electricity and heat.
This property is crucial for many applications of metals in electrical and thermal systems.
What does it mean for metals to be malleable?
It means that the layers of atoms in a metal can slide over each other, allowing metals to be bent, hammered, or rolled into flat sheets.
Malleability is a key characteristic of metals, making them versatile for various uses.
What are alloys?
Alloys are mixtures of two or more metals or a metal and another element, often making them harder than pure metals.
Alloys are commonly used in everyday applications due to their enhanced properties compared to pure metals.
Why are alloys harder than pure metals?
Different sized atoms in alloys distort the layers of metal atoms, making it more difficult for them to slide over each other.
This distortion increases hardness and strength, making alloys more suitable for certain applications.
Fill in the blank: Metallic bonding is characterized by _______.
delocalised electrons.
True or False: Most metals are liquid at room temperature.
False.
What are the three states of matter?
Solid, Liquid, Gas
What factors determine the state of a substance?
Structure of the substance, temperature, pressure
In solids, how are the particles arranged?
Strong forces of attraction hold them close together in a regular lattice arrangement
Do solids have a definite shape and volume?
Yes
What happens to the particles in a solid when it is heated?
They vibrate more and the solid expands slightly
In liquids, how do the particles behave?
They are randomly arranged and free to move past each other but tend to stick closely together
Do liquids keep a definite shape?
No, they take the shape of their container
What happens to the particles in a liquid when it is heated?
They move faster, causing the liquid to expand slightly
In gases, how are the particles arranged?
They are far apart and move freely
Do gases have a definite shape or volume?
No, they fill any container
What is particle theory?
A model that explains how particles in a material behave
What is the behavior of gas particles when heated?
They move faster, causing expansion or increased pressure
What are state symbols used for in chemical equations?
To indicate the physical state of reactants and products
What does (s) represent in state symbols?
Solid
What does (l) represent in state symbols?
Liquid
What does (g) represent in state symbols?
Gas
What does (aq) represent in state symbols?
Aqueous
Fill in the blank: Aqueous means _______.
dissolved in water
What is an example of a chemical reaction with state symbols?
Aqueous hydrochloric acid reacts with solid calcium carbonate to form aqueous calcium chloride, liquid water, and carbon dioxide gas
True or False: Particle theory accurately depicts particles as solid spheres.
False
What is one limitation of particle theory?
It does not show the forces between particles
What happens to particles when a solid is heated?
Particles gain more energy and vibrate more
This increased vibration weakens the forces holding the solid together.
What is the term for the process when a solid turns into a liquid?
Melting
This occurs at the melting point when particles have enough energy to break free from their positions.
What occurs at the melting point?
Particles have enough energy to break free from their positions
This leads to the transition from solid to liquid.
What is the process called when a liquid turns into a solid?
Freezing
This occurs when particles lose energy and bond more strongly.
What happens to particles when a liquid cools?
Particles have less energy and move around less
This allows more bonds to form between particles.
What is the boiling point?
The temperature at which particles have enough energy to break their bonds, leading to boiling
This process transforms a liquid into a gas.
What is the process called when a gas turns into a liquid?
Condensing
This occurs when gas particles lose energy and form bonds.
What happens to particles when a liquid is heated?
Particles gain even more energy and move faster
This weakens and breaks the bonds holding the liquid together.
What is the energy needed for a substance to change state dependent on?
The strength of the forces between particles
Stronger forces require more energy to break, resulting in higher melting and boiling points.
If the temperature is below the melting point of a substance, what state will it be in?
Solid
The substance remains solid until the melting point is reached.
If the temperature is above the boiling point of a substance, what state will it be in?
Gas
The substance will be in gaseous state above its boiling point.
What state will a substance be in if the temperature is between the melting point and boiling point?
Liquid
This indicates that the substance has partially overcome the attractive forces between particles.
Which molecular substance is a liquid at room temperature (25 °C) among oxygen, nitrogen, and bromine?
Bromine
Bromine has a melting point of -7 °C and a boiling point of 59 °C, making it a liquid at room temperature.
True or False: An atom on its own has the same bulk properties as a material composed of many atoms.
False
Bulk properties depend on how many atoms interact together.
