Bonding, Structure and Properties of Matter Flashcards
what are ions
ions are charged particles
how do metals form ions and what ions do they make
they lose electrons from their outer shell to form positive ions
how do non metals form ions and what ions do they make
they gain electrons into their outer shell to form negative ions
what is ionic bonding and what happens
ionic bonding is the transfer of electrons from a metal and a non metal. The metal atom loses an electron to form a positively charged ion and the non metal gains these electrons to form a negatively charged ion.
how can you show how ionic compounds are formed
dot and cross diagrams
what structure do ionic compounds have
giant ionic lattice
what’s inside an ionic compound
the ions inside an ionic structure form a closely packed regular lattice arrangement and there are strong electrostatic forces of attraction between oppositely charged ions in all directions in the lattice
properties of ionic compounds
high melting and boiling point because of the strong bonds between them
can only conduct electricity when molten or dissolved because the ions need to be free to move
what is covalent bonding
covalent bonding is the sharing of electrons between two non metals so that they can have a full outer shell
properties of simple molecular substances
very strong covalent bonds but have weak intermolecular forces
low melting and boiling points because of the weak intermolecular forces
do not conduct electricity
what is a polymer
are many monomers joined together
how are atoms in a polymer joined together
by strong covalent bonds
giant covalent structures properties (3)
strong covalent bonds
very high melting and boiling point
do not conduct electricity
what are allotropes
allotropes are different structural forms of the same element in the same physical state
diamond properties 4 things
made up of carbon atoms
each carbon atom forms four covalent bonds making them very hard
very high melting point because of the strong covalent bonds
does not conduct electricity as it has no free electrons
graphite properties (6)
made up of carbon atoms
each carbon make 3 covalent bonds
graphite is in sheets
theyre soft due to the layers being able to slide over each other
conducts electricity due to the spare electron
high melting point
graphene 3 things
is a single sheet of carbon atoms
very strong because of its network of covalent bonds but very light which makes it useful
contains delocalised electrons which makes it able to conduct electricity
what are fullerenes
fullerenes are molecules of carbon
uses of fullerenes 3 things
can be used to cage other molecules this can be used to deliver drugs
can be used as a catalysts because of its huge surface area
good lubricants
metallic bonding
metals are made up of positive atoms in a sea of delocalised electrons
properties of compounds with metallic bonds (4)
strong electrostatic forces
high melting and boiling point
good conductors of heat and electricity
the metals are malleable
why are alloys more useful than pure metals
alloys are much harder than pure metals as they are a mixture between two or more metals or a metal and another element
pure metals are too soft
why are alloys harder that pure metals
when another metal is mixed with a pure metal to make an alloy the new metal atoms will distort the layers of metal atoms making it more difficult for them to slide over each other. This makes alloys harder than pure metals.
Why is iron described as an element?
because iron is made up of only one type of atom
The three metals in stainless steel have different sized atoms. Stainless steel is harder than pure iron.
the structure of stainless steel is distorted making it hard for the layers to slide over each other
Name the instrument used to identify the compounds.
mass spectrometer
Give one reason why instrumental methods of analysis are used to identify the compounds
more accurate
Suggest two conditions which could be changed when poly(ethene) is made.
pressure
temperature`
2 KI(aq) + Pb(NO3)2(aq) → 2 KNO3(aq) + PbI2(s)
why is this reaction a precipitation
a solid was formed
How can the precipitate be removed from the reaction mixture?
filtering
Describe the structure of a metal.
3
lattice of positive ions with delocalised electrons
alloy =
mixture of metals
Bronze is an alloy of
copper and tin
What is the carat number of pure gold?
24
A nanodiamond contains a few
hundred atoms
in diamond ______ atoms are bonded together
all
Explain why chlorine (Cl2) is a gas at room temperature, but sodium chloride (NaCl) is a solid at room temperature.
chlorine
covalent bonds between the atoms forming simple molecules.
there is a weak attraction between the molecules meaning that it has a low boiling point
sodium chloride
electrostatic attraction in all directions between oppositely charged ions forming a giant lattice.
large amount of energy needed to break the bonds, it has a high boiling point
Pb(NO3)2(aq +K2CrO4(aq)⟶PbCrO4(s)+2KNO3(aq)
what would you see
a precipitate
Na2CO3(aq) + 2HCI(aq)⟶2NaCl(aq) +CO2(g)+H2O(I)
Explain why this student’s results would not appear to support the law of conservation of mass.
co2 is a gas
the gas escapes during the reaction
so the mass at the end is less than expected
In silicon dioxide, each silicon atom is bonded with ____ oxygen atoms.
four
describe the structure and bonding of a metal.
giant structure
made up of positive ions surrounded by delocalised electrons with strong bonds
so a lot of energy is needed to break these bonds
Like graphite, each carbon atom in the carbon nanotube is joined to three other carbon atoms.
Explain why the carbon nanotube can conduct electricity.
it has delocalised electrons
it has one non bonded electron from each atom
explain why graphite conducts electricity
graphite is made out of carbon atoms
each carbon atom forms 3 covalent bonds
one electron per carbon is delocalised
these electrons carry charge through the graphite
explain why you would not expect titanium chloride to be a liquid at room temperature
titanium is a metal chloride
metal chlorides are usually ionic so metal chlorides are solid at room temperature because they have strong forces between ions
