chemistry Flashcards
tell me the details of the periods
- they are horizontal
- they tell us how many occupied shells there are
- all elements in the same period have the same number of occupied energy shells
tell me the details of groups
- they are vertical
- they tell us how many electrons are on the outer shelll
- all elements in the same group have thw same number of of electrons in their outer shells
where are non metals
on the right
solid to liquid?explain
melting
Particles gain kinetic energy and
vibrates faster, allowing particles to
overcome forces of attraction that
hold them together in the solid
liquid to solid? explain
freezing
Particles lose kinetic energy,
allowing forces of attraction
between the particles to hold them
together
liquid to gas? explain
evaporating
Particles gain kinetic energy and
move further apart, causing the
forces of attraction between them
to be completely broken
gas to liquid? explain
condensation
Particles lose kinetic energy and
vibrates faster, allowing forces of
attraction to bring particles closer
together
what state are metal oxides at room temp
solid
are metal oxides soluble or insoluble in water
insoluble
what state are non-metal oxides at room temp
solids or gases
are non-metal oxides soluble or insoluble in water
soluble
what do non-metal oxides from in water
acids
group one physical properties
- soft
- float in water
- only shiny when freshly cut
- stored in oil
what happens with lithium and water
- it floats and efferveces
- gets small until it dissapears
what does lithium and water make (pH)
a strong alkali (blue/purple)
lithium + water…
lithium hydroxide + hydrogen
how to know if a gas given off is hydrogen
squeaky pop with a lighted spling
what does sodium do different than lithium in water
- it melts into a silver colored ball
- it moves around faster and efferves more
what color is a sodium flame
yellow
sodium + water…
sodium hydroxide + hydrogen
what does potassium do differenly than sodium when reacting with water
it moves around faster and effereveces more
what flame color does potassium turn
lilac flame
potassium + water…
potassium hydroxide + hydrogen
what happens with rubidium and water
it immediatley sparks and almost looks like fireworks
what happens with water and caesium
it pops and then produces like fireworks and it is extremely powderful that it causes the glass to break
group 1 metals + water…
metal hydroxide + hydrogen
what do all group 1 metals form with water
alkalis
does the reactivity increase or decrease down group 1
increase
why does the reactivity in group 1 increase going down
all atoms in group one only have 1
electron in their outer shell which
means in chemical reactions they
lose the outer electron to become
more stable
the outer shell is further from the
nucleus as you go down so it is
more easily lost causing there to be
a stronger reaction
what do all group 7 elements have in common
- they are all non metals
- they have 7 electrons in their outer shelll
what are the physical properties of group 7
- they are all made up of diatomic molecules
- they are made up of 2 atoms bonded together
why is iodine unusual
when it is heated it sublimes (changes directly from a solid to a gas)
trends down group 7
- reactivity decreases
- elements get darker in color
- metling and boiling points increase
what is the chemical test for chlorine
use damp blue litmus paper
result - the paper turns white if chlorien is present
chlorine and hot iron wool
the iron glows brightly
a reddish-brown solid called iron(III) chloride is formed
bromine and hot iron wool
the wool will only react is the bromind vapour is heated consistantly
it will glow but not as brightly as chlorine
it produces iron(III)bromide
iodine and hot iron wool
they react very slowly
the only evidence is a reddish brown solid called iron(III) iodine
what do all group 7 elements produce with iron
Halides
what happens in group 7 chemical reactions
group 7 electrons gain an electron to achieve a full outer shell
why does reactivity decrease in group 7
as we go down the outer shell is
further from the positive nucleus so
the incoming electron feels a
weaker attraction so it is less easily
gained
how are the halogens formed
ionic compounds
called metal halides
what is the aim of the displacement reaction
the aim of the displacement
reactions is to take a free halogen
elecent (Cl,Br,I) and see if it reacts
with a group one metal halide
(KCl,KBr,KI)
what happens if a free halogen reacts with a group one metal halide
it changes color
chlorine water + potassium bromide solution…
bromine water + potassium chloride
how is a solution made
when a solid is dissolved in a liquid
what is a concentrated solution
one which has a high proportion of a solute
what is a dilute solution
one wich has a small amount of solute
what is a saturated solution
one which no more will dissolve at that temperature
units of solubility
g/100g of water
what is the solubility of a solute
the mass in grams of the solute that will dissolve in 100g of solvent at a certain temperature
solubility curve
solutbility on y axis
temperature on x axis
what are chemical reactions
the movement of electrons
where does ionic bonding occur
between a metal and non metal
what is an ionic bond
an ionic bond is the strong electrostatic force of attraction between oppositley charged ions in a giant structure
what does it imply is sodium is a solid with a high melting point at room temperature
if it has a high melting point it means the bonds must be so strong that they are hard to overcome
what is sodium chloride made of
positively charged sodium ions
negitivley charged chloride ions
what is a giant structure in sodium chloride
millions of sodium chloride ions in one sodium chloride crystal
how does the sodium chloride ion form
each sodium atom looses one
electron to a chloride atom so that
both achieve a full outer shell of
electrons
The sodium atom becomes
positively charged
The chlorine atom becomes
negatively charged
what must substances have to conduct electricity
charged free moving particles
written explination of magnesium fluoride
each magnesium atom has 2
electrons in its outer shell. each
fluorine atom needs 1 more
electron to have a full outer shell.
This means 2 fluorine atoms are
needed for each magnesium atom.
A magnesium atom transfers 1 of
its outer shell electrons to one
fluorine atom and the second outer
shell electron to the other fluorine
atom. The magnesium atom
becomes positively charged and
the fluorine atom becomes
negatively charged fluoride ion
the ratio is 1:2
structure of metals
metals consist of a giant structure
of millions of regularly arranged
positive ions surrounded by a ‘sea’
of delocalized electrons
what is a metallic bond
The metallic bond is the strong
electrostatic force of attraction
between the positively charged
metal ions and the negatively
charged delocalized ions
where is metalic bonding present
metallic bonding is present in
metal elements such as iron,
copper, silver, gold and more
what is an alloy
a mixture of a metal and non metal and usually one or more other elements
why are alloys not as malleable as metals
the 2 elements are not the same
size which disrupts the layers
causing them to not slide over
each other
melting point of metals and why
metals have a high melting point
because they have a giant structure
and these strong electrostatic
forces of attraction require a lot of
thermal energy to overcome them
why are metals good conductors of energy
they have
delocalised electrons which are free to move
why are metals malleable and ductile
the layers of metal ions in
the structure can slide over one
another without disrupting the
bond
