Testing for Ions Flashcards
What is meant by the term malleable?
Bent/changed into shape
Explain in Terms of it’s structure why magnesium is Malleable?
-layers or atoms can slide over each other
state one industrial use for diamond?
Diamond drill bits
Diamond and graphite both have high melting points explain why?
- stron cobalent bonds
- require lots of energy to break
Fe2+ Fe3+ Cu2+ Li+ Na+ K+ Ca2+ Name these common ions
Iron 2+ Iron 3+ Copper2+ Lithium calcium potassium Calcium2+
Iron(II) solution with sodium hydroxide forms a
gelatinous green precipitate
Iron (III) solution with sodium hydroxide forms a
brown precipitate
Copper(II) with sodium hydroxide forms a
blue precipitate
Lithium produces what colour flame in the flame test?
Red
Pottasium in the flame test
lilac
sodium in the flame test
yellow
calcium in the flame test
brick red
Test for aninon: add hydrochloric acid what happens
carbonate gives off effervescence
-gas turns limewater milky-CO2
Name the three halide ions
chloride
bromide
iodide
add nitric acid +silver nitrate solution to chloride-
forms a white precipitate
add nitric acid and silver nitrate solution to bromide
cream precipitate with silver nitrate
add nitric acid and silver nitrate
yellow precipitate with silver nitrate
add hydrochloric acid and barium chloride solutions
sulphates give white precipitates or barium sulphate
What must be used for a flame test wire?
inert metal
method for the flame test?
- dip the wire into the test substance
- place the wire and the test substance on the side of a roaring flame or (non luminous) bunsen flame
Hydroxide precipitate test method
- place 1cm cubed of test solution into test tube if given a substance as a solid it must first be dissolved in water to make a solution
- add drop by drop sodium or (potassium) hydroxide solution and mix gently
- record observations
What are three ionic compounds that contain ammonium
Ammonium Chloride
Ammonium hydroxide
ammonium sulphate
Method to test compound containing ammonium
- add a few CM3 of sodium hydroxide solution
- gently warm test tube
- hold a piece of damp red litmus paper at the mouth of the test tube
- If ammonia gas is released red litmus turns blue
What happens if test compound contains ammonium ions
ammonia gas is released
why do we use distilled water when making a solution
distilled water doesn’t contain other ions
when testing for sulphate ions why use dilute hydrochloric acid?
to remove other ions that can form a precipitate with barium chloride solution
what is the word equation for barium and copper sulphate
Copper sulphate + Barium Chloride > barium sulphate (white ppt) + copper chloride
