Unit 5 :P Flashcards
What is the test and positive observations for the halogens?
Reflux with NaOH(aq) and add AgNO3 (aq).
Cl- will give a white ppt
Br- will give a cream ppt
I- will give a yellow ppt
What are some tests for phenol?
Bromine water- a colour change from orange to colourless is observed as a white ppt of 2,4,6-tribromophenol is formed
Iron (III) chloride- a purple solution is formed?
What are the group 2 metal ions reactions with NH4+?
Mg2+ - white ppt of Mg(OH)2 formed
Ca2+ - no observable change
Sr2+ - no observable change
Ba+ - no observable change
What are the group 2 metal ions reactions with excess OH-?
Mg2+ - white ppt of Mg(OH)2 formed
Ca2+ - white ppt of Ca(OH)2 formed
Sr2+ - slight white ppt of Sr(OH)2
Ba2+ - no observable change
What are the group 2 metal ions reactions with excess SO4-?
Mg2+ - colourless solution formed
Ca2+ - slight white ppt of CaSo4 formed
Sr2+ - white ppt of SrSO4 formed
Ba2+ - white ppt of BaSO4 formed
What is the test for CO3^2-?
Add dilute HCl and pipette the gas formed into limewater. The limewater should turn milky when the gas is bubbled through.
What are the observations of the different metals for the flame test?
K+ - lilac flame
Na+ - yellow/orange flame
Ca2+ - brick red flame
Li+ - crimson red flame
Ba+ - apple green flame
What is the test for carbonyl groups?
Add Brady’s, an orange-red solid should form.
What is the test for aldehydes?
Add Tollens reagent, and a silver mirror should be produced.
What is the test for methyl ketones?
Add iodoform and pale yellow crystals should be produced.
What is the test for alchohols?
Add H+/Cr2O72-, and a orange to green colour change is observed.
What is the test for carboxylic acids?
Blue litmus paper turns red. Adding NaHCO3 will produce effervescence and bubbles of CO2.
What is the test for amines?
Red litmus paper turns blue.
What is the test for amides?
Alkaline hydrolysis, OH-/H2O produces NH3 gas.
