C2 Periodic table Flashcards
how and what did Newlands discover
building on Dalton’s idea he arranged elements in order of mass and noticed that properties of every 8 elements seemed similar (law of octaves)
what didn’t Newlands consider
unfound elements
how did mendelev arrange the elemets
1869 by atomic weights, left gaps for ellemts that had not been discovered
example of elements that did,’t fit in mendelev’s table
argon(greater relative mass) and potassium
this was later solved when noble gases where discovered
what does gropu number tell you
number of electrons in the outmost shell, so every group has similar properties
characterestics of metals
metallic bonding
conduct electricity, higher boiling and melting points, ductile and malleable
characteristics of non metals
electronic insulators, if solids are brittle
where can you found non-metals
top right hand corner
what groups do atoms of elements gain electrons to form negative ions
5,6,7
where can you found metals
left hand side and centre
which groups lose electrons to form positive ions
metals of group 1,2,3
n. of electrons in outmost shell of noble gases
8 so very stable
why are noble gases very unreactive
very stable electon arrangement
when can large noble gases make compounds
with the mosr reactive non metals
what’s the first group name
alkali metals
examples of alkali metals
lithium, sodium potassium
properties of alkali metals
- very reactive, must be stored in oil so don’t react with O
- reactivity increases as you go down the group
- very low densities, FLOAT ON WATER
- very soft
- silvery shiny surface when you cut them until don’t react with O
electronic structure of alkali metals
1 electron in outmost shell
with who and how do alkali metals react
with non metals losing the single electron in the outer shell, so form positive ion with +1 charge(always form ionic compounds)
how do melt and boil points get lower for alkali metals
as you go down the group
how do alkali metals react with
- water
- oxygen
metal flouts moving around and fizzing-caused by reaction with water to form hydrogen gas
2. also produces metal hydroxides which are soluble , solution colorless with high pH
colour of reaction between alkali metals and non-metals
solutions formed colourless, dossolve in water
what are halogens + examples
gropu of toxic non metals that have coloured vapours fluorine chlorine nromine iodine
what are the melting points and boiling for halogens
low, increase going down
are they good conductors (halogens)
poor conductors of electricity and heat
structure and its name of halogens
they exist as molecules made up of pairs of atoms, diatomic molecules, atoms joined by a covalent bonnd
n of electrons in outmost shell of halogens
7
what happen in terms of electrons movements when halogens react with non-metals
gain extra electron by sharing a pair of electrons with another atom, covalent bonds , form molecular compounds
halogens also react with metals to…..
gain a single electron, ionic bonding
what are transition elements
all metals in the large central block
physical properties of transition elements
hard and strong
good conductors of electricity and thermal energy
high densities
high melting point(except mercury)
all of these characteristics are greater than alkali metals’
are transition elements reactive
less reactive than metals in gruop 1
how do transition elements react (+with O or water)
don’t react so vigorously
they usually form positive ion
where are transition elements used
structural materials because of chemical and physical properties
what do transition elements form
coloured compounds
name of a compound of a transition element includes…
roman number because they can form more than 1 ion
examples of transition elements
iron, nickel, copper, titanium
examples of compund from transition el.
copper(II) sulfate = blue
nickel(II) carbonate= pale green
how are transition elements and their compund used in chemical industry
catalyst
eg. iron in harber process
