C2.6 - the transition metals Flashcards
(33 cards)
differences between transition metals and group 1
- Compared to group 1 elements, transition metals have different physical properties.
For example transition metals have a higher melting point and are more dense. - The exception is mercury which is a liquid at room temperature.
- Transition metals also have different physical properties to group 1. They are much
less reactive and do not react vigorously with oxygen or water.
where are the transition metals on the periodic table
The central block (between group 2 and 3) of the Periodic Table is known as the
transition metals.
how are flame tests carried out?
- Dip metal loop in dilute HCl, hold in Bunsen burner flame (blue flame), until no
colour is seen. - Dip the loop into the sample you are testing
- Place this into the flame and observe the colour
flame test for sodium
Sodium (Na+) = Yellow
flame test for lithium
Lithium Li+ = Crimson
flame test for potassium
Potassium K+ = Purple
flame test for copper
Copper Cu2+ = Green
flame test for calcium
Calcium Ca2+ = Red/Orange
what is the test for insoluble metal hydroxides
drops of sodium hydroxide are added to a solution of the metal hydroxide a precipitate may form.
Transition metal hydroxides are usually coloured
Main group elements normally form a white precipitate.
metal hydroxide test for aluminium ionic equation
Al3++ 3OH- -> Al(OH)
metal hydroxide test for magnesium ionic equation
Mg2++ 2OH- -> Mg(OH)2
metal hydroxide test for calcium ionic equation
Ca2++ 2OH- -> Ca(OH)2
calcium + hydroxide = calcium hydroxide
metal hydroxide test for Iron(II) ionic equation
Fe2++ 2OH- -> Fe(OH)2
metal hydroxide test for Iron(IIl) ionic equation
Fe3++ 3OH- -> Fe(OH)3
metal hydroxide test for copper ionic equation
Cu2++ 2OH- -> Cu(OH)2
what is the test for halides
Add 5 drops of dilute nitric
acid and 5 drops of silver nitrate
The colour of the
silver halide precipitate
formed will vary depend on
the halogen
what colour is the halide: chloride
White
what colour is the halide: bromide
Cream
what colour is the halide: iodide
yellow
what is the test for the negative ion, carbonate (CO3 2-)
- Add metal carbonate to dilute
acid in a boiling tube. - Connect
the boiling tube to a test tube
containing limewater.
what is the positive result for carbonate (CO3 2-)
If the
limewater turns cloudy then a
carbonate ion is present
K2CO3+2HCl -> 2KCl+CO2+H2O
what is the test for the negative ion sulphate (SO4 2-?
- Add 5 drops of dilute hydrochloric acid (HCl)
- Then add 5 drops of barium chloride.
what is the positive result for sulfate?
If sulphate
ions are present then a white
precipitate will be formed.
Ba2++ SO42–>BaSO4
(This is the ionic equation
for the reaction. )
what is the test for halides (chloride, bromide, iodide)
Add 5 drops of dilute nitric
acid and 5 drops of silver
nitrate
