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Discussion:

Question (1)

Write all the balance equations for each reaction and any observations.

Qualitative analysis is often use to analyses the substance in which they

are identied or classied on the basis of their chemical and physical properties

such as chemical reactivity appearance of compound solubility molecular

wei!ht meltin! point radioactive properties (emission and absorption) mass

spectra and nuclear half"life. While quantitative analysis is more often use to

analyses the amount or concentration of an analyte may be determined and

e#pressed as a numerical value in appropriate units. $n this e#periment we are

conductin! the qualitative analyses which is separate into two part of

e#periments. $n the rst part we were more focused on the %nown compound

while in the second part we more focused into predictin! the ions that present in

the un%nown compound.

&or part ' the result above shows that solid iron ($$$) chloride (&e  Cl

3 ) is

white in colour and has crystal shape lead ($$) nitrate b(  0

3¿2  is yellow in

colour and in crystal powder while calcium carbonate *a*  o

3  is white in colour

and in crystal powder shape.

&e  Cl

3  (s) + H 

2 , (l) -

3+¿

 Fe¿ (aq) +

−¿

3Cl¿

b(  0

3¿2  +

 H 2 , (l) -

2+¿

 Pb¿  (aq) + ,/

" (aq)

When dissolved in water iron($$$) chloride under!oes hydrolysis and !ives o0

heat in an e#othermic reaction

&or the solubility of water only calcium carbonate is not soluble in water. his is

because to be soluble in water there must be the presence of *  O

2  calcium

carbonate will react with water that is saturated with carbon dio#ide to form the

soluble calcium bicarbonate.

*a*,/ + *  O

2  + H 

2 , - *a(2*  O

3¿2

 his reaction is important in the erosion of carbonate roc%s formin! caverns and

leads to hard water in many re!ions. 'n unusual form of calcium carbonate is the

he#ahydrate i%aite *a*,/342,. $%aite is stable only below 4 5*.

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&or the solubility test of nitric acid 2  O

3  the observation that

had been !ather shows that iron ($$$) chloride (&e  Cl

3 ) in nitric acid form

bubles.

&e  Cl

3 (s) + 2,/ (aq) - &e(,/) (aq) + /2*l(aq)

iron ($$$) chloride (&e  Cl

3 ) react with nitric acid and form ferric chloride. hat is

why there is bubbles formed. he precaution are we must ma%e sure all

compound are handle properly. Do not over ll the boilin! tube.

6eaction with sodium hydro#ide (a,2). ,nly calcium carbonate for a

white precipitation.

*a*,/(s) + a,2(aq) - *a(,2)(aq) +a*,/(aq)

7 have to stir until a precipitate form.

6eaction with ammonia (2/) carbon carbonate and iron ($$$) chloride form

white precipitate.

&e*l/(s) + 2/ (aq) - &e(2/) (aq) + /a*l (aq)

*a*,/ (s) + 2/ (aq) - *a(2/) (aq) + *, (aq) + , (!)

 here are some error on doin! the e#periment. 8ome of it are the step ondoin! the e#periment are suppose to brin! result but it turns out the result show

di0erently.

art 9

$dentify the cations and anions for the un%nown compounds.

*ation identication test.

*ompound D is cation positive because bri!ht !reen colour chan!e to red

colour is indicate that it has *2. $t is cation positive. *ompound ; is cation

positive. he solution turned blue litmus paper to red and red litmus paper

unchan!ed. 'nions are contributed by acids therefore they are called as acid

radicals this is due to the acidity properties. he solution also chan!e from yellow

to dar% brown. hus the cation is %nown as ferric ion (&e/+). &or compound &

the solution produce a white precipitate. $t<s an anion positive. he presence of

,/" indicates that it has anion positive. &or compound = its o#idise durin! the

reaction for hours and formed white precipitate. $ts has 8," that is anion

positive.

 here are some precaution step that must be ta%en to obtain the correct

result for this e#periment. &irstly we used the micro centrifu!e tubes throu!houtthis procedure. he tubes can hold either 1.> or .? m@ (listed on the tube). $f

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the volume of your solution e#ceeds that of the tube separate the solution into

two tubes and treat each one accordin! to the Aowchart so that the solution does

not fell into the table. 9esides precipitation after the addition of a precipitatin!

a!ent it is important to mi# the solution thorou!hly by sha%in! or by stirrin! with

a clean !lass stir rod. 9e sure not to add more of a precipitatin! a!ent than

indicated in the procedure as this may cause unintended reaction that can a0ect

our e#periment. itric acid hydrochloric acid and sodium hydro#ide are corrosive

and can cause severe inBury. ever cover the openin! of a test tube with your

n!er when mi#in! chemicals and we should wear !loves for the e#periment we

conducted. @astly it is also necessary to %now the correct way to ma%e the test

for the litmus paper. he correct method for ndin! the chan!es on the litmus

paper of a solution involves stirrin! the solution with a clean !lass rod and then

touchin! the tip of the rod to a piece of litmus paper. Do not place the litmus

paper directly in the solution.

*onclusion:

 he e#periment show us how we identied each of the compound react

with other solution. he e0ect on other substance. We could identied the

specic ion on the cation and anion identication test. $n quantitative analysis weclassify features while qualitative analysis is a complete detailed description.

6eference:

References:

• Bogdan, R.C. and Taylor, S.J., (1975) Introduction to qualitative research methods: A

 phenomenological approach to the social sciences, Boston: Allyn & Bacon.• Mils, M.B. and !"#r$an, A.M. (19%). Qualitative Data Analysis: A Sourcebook of 

 New ethods, Sag '"#lications, #"ry 'ar*, CA.

• +ang (1999). !andbook of "hemistry (15t d.). CRC nt Bas -rod"ction.

• tt-:./ias.orggnc$inorgco$-0sodi"$ydroid.t$l

• tt-:.-"#lic.as".d"23-#ir*4"al4"alanallad.t$l