1What is a salt
It is a compound formed when some or all of the hydrogen ions in an acid are replaced by metal ions or ammonium ions
2What are the 2 types of ions in a salt
Positve (Cation) and Negative (Anion)
3What are the reagents used to identify cations
Aqueous sodium hydroxide and aqueous ammonia
4Metal salt + sodium hydroxide gives?
Metal hydroxide + sodium salt
5Copper (II) chloride + sodium hydroxide gives?
Copper (II) hydroxide + sodium chloride
6Metal salt + aqueous ammonia gives?
Metal hydroxide + ammonium salt
7Copper (II) choride + aqueous ammonia gives?
Copper (II) hydroxide + ammonium chloride
8What is the outcome when testing for ammonium cation with aqueous sodium hydroxide
No precipitate. On warming, pungent gas which turns moist red litmus paper blue is evolved. The gas is ammonia.
9What is the outcome when testing for aluminium cation with aqueous sodium hydroxide
white precipitate; soluble in excess to form a colourless solution
10What is the outcome when testing for aluminium cation with aqueous ammonia
white precipitate; insoluble in excess
11What is the outcome when testing for zinc cation with aqueous sodium hydroxide & aqueous ammonia
white precipitate; soluble in excess to form a colourless solution
12What is the outcome when testing for calcium cation with aqueous sodium hydroxide
white precipitate; insoluble in excess
13What is the outcome when testing for calcium cation with aqueous ammonia
no precipitate
14What is the outcome when testing for Copper(II) cation with aqueous sodium hydroxide
blue precipitate; insoluble in excess
15What is the outcome when testing for Copper(II) cation with aqueous ammonia
light blue precipitate; soluble in excess to form a dark blue solution
16What is the outcome when testing for Iron(II) cation with aqueous sodium hydroxide & aqueous ammonia
green precipitate; insoluble in excess
17What is the outcome when testing for Iron(III) cation with aqueous sodium hydroxide & aqueous ammonia
red-brown precipitate; insoluble in excess
18What is the test & its result for carbonate anion
Add dilute acid and bubble the gas evolved into limewater. Effervecence is observed and the gas (carbon dioxide) forms white precipitate (calcium carbonate) in the limewater
19How to write an equation for testing carbonate anions?
Metal carbonate + Dilute Acid → Metal salt + water + carbon dioxide
20What is the test & its result for chroride anion?
Add dilute nitric acid then add aqueous silver nitrate. White precipitate (silver chloride) is observed
21How to write an equation for testing chloride anions?
Metal chloride + Silver nitrate → Silver chloride + Metal nitrate
22What is the test & its result for sulfate anion
Add dilute nitric acid, then add aqueous barium nitrate/aqueous barium chloride. White precipitate (barium sulfate) is observed
23How to write an equation for testing sulfate anions?
Metal sulfate + Barium chloride → Barium sulfate + Metal chloride
24What is the test & its result for nitrate anion
add aqueous sodium hydroxide then aluminium foil; warm carefully Test for gas by placing a moist red litmus paper at the mouth of test tube. Effervescence observed. Pungent gas (ammonia) turns moist/damp red litmus paper blue
25What is a test of ammonia
when it turns moist red litmus paper blue
26What is a test for carbon dioxide
gives white precipitate with limewater (white ppt dissolves when excess CO2 is bubbled into limewater)
27What is a test for chlorine
moist blue litmus paper turns red and bleaches white
28What is a test for hydrogen
extinguishes lighted splint with a ‘pop’ sound
29What is a test for oxygen
relights / rekindles glowing splint
30What is a test for sulfur dioxide
turns aqueous acidified potassium manganate(VII) from purple to colourless