EL7 Flashcards
+1 cations
H, Li, Na, K, NH4
+2 cations
Mg, Ca, Ba, Fe (II), Cu (II), Zn, Pb (II)
+3 cations
Fe (III), Al
-1 anions
F, Cl, Br, I, OH, NO3, HCO3
-2 anions
O, CO3, SO4
test for Cu (II), Fe (II) and Fe (III) ions
add sodium hydroxide, precipiate formed:
blue copper hydroxide
green iron (II) hydroxide
orange/brown iron (III) hydroxide
test for Pb (II) ion
add potassium iodide, precipitate of yellow lead iodide formed
test for chloride, bromide and iodide ions
add silver nitrate, precipitate formed:
white silver chloride
cream silver bromide
yellow silver iodide
test for sulfate ions
add barium chloride, precipitate of white barium sulfate formed
properties of ionic compounds
often soluble in water, insoluble in polar solvents
typically solids at RTP
very strong electrostatic attractions - high MP and BP
conduct electricity when molten/dissolved as ions are free to move
properties of metallic compounds
insoluble in water and non-polar solvents
lattice structure of metal cations in a sea of delocalised electrons
electrons free to move, good conductors
electrostatic attraction between cations and delocalised electrons - high MP and BP
properties of covalent networks
insoluble in water and non-polar solvents
large covalently bonded structures
high MP and BP
don’t conduct electricity - no charged particles
properties of simple covalent molecules
usually insoluble in water (unless can form H bonds), usually soluble in non-polar solvents
weak intermolecular bonds, low MP and BP
don’t conduct electricity due to lack of charge particles
properties of macromolecules
usually insoluble in water, sometimes soluble in non-polar solvents
polymers and long chain molecules
fairly weak intermolecular bonds - moderate MP and BP
don’t normally conduct electricity
