8.3 Quantitative analysis

Question 1

how do you carry out the carbonate test?

Answer 1

+ dilute HNO3
positive: bubbles
to prove the bubbles are co2 bubble it through lime water Ca(OH)2
itll go cloudy/milky

Question 2

how do you carry out the sulfate test?

Answer 2

+ Ba+ ions
Positive test: heavy white precipitate

BaCl2 or Ba(NO3)2 can be used but barium nitrate is prefered if a halide test folows

Question 3

How do you carry out a halide test?

Answer 3

+ AgNO3
Silver halid precipitates
AgCl white
AgBr cream
AgI yellow

+ amonia
Cl soluble in dilute
Br soluble in conc
I insoluble

Question 4

what is the sequence of quantative analysis and why is it important?

Answer 4

1. Carbonate test - sulfate nor halide will form bubbles so no chance of false positive, continue to add HN03 until no more bubbles form all co3 has reacted dont use HCL or H2SO4 theyll give false positves later down
2. Sulfate test, any leftover carbonate ions can give a false positive, any sulfate ions will precipitate out as Ba(N03)2, filter to remove the excess Use Barium nitrate no barium chloride
3. halide test any precipitate will be a halide dd NH3 to confirm wich