Periodic Table Flashcards
Newlands arranged his periodic table how?
order of atomic mass and similarities every 8th element.
why did newlands idea not work?
not all properties every 8th where the same?
what was unique about Mendeleev’s periodic table?
he left gaps where there where undiscovered elements
what did Mendeleev’s periodic table allow him to do?
predict the atomic masses and properties of undiscovered elements.
how is the modern periodic table arranged?
on atomic numbers.
group 1 is known as what?
alkali metals
properties of group 1
- low density
- react with water to make hydrogen
- form hydroxides that dissolve in water, gives alkali solution.
transition metals are have what boiling and melting points?
much higher melting and boiling points than group 1
transition metals are often
harder and stronger than group 1 metals and less reactive too
transition metals are what as catalysts?
useful as catalysts.
transition metals can form what compounds?
coloured compounds.
group 7 elements are known as
halogens
when a group 7 atom produces an ion it is known as a
halide
the further down group 1 the
- less reactive the element is
- higher the melting and boiling points
the higher the energy level of the outer electron shell the
more easy electrons are lost, the less easy electrons are gained.
