UPDATES 4 ALL WAEC 2013 PRACTICAL SPECIMENS (CHEMISTRY, AGRIC. &BIOLOGY WITH QUESTIONS TO EXPECT)
AGRIC SPECIMENS..
A= sandy soil (to be labelled).
B= loamy soil.
C=clay soil.
D= pebbles or sand stone.
E= granite.
F= marble.
G= litmus paper (blue and red).
H= dilute HCl (to be labelled.
I=shears.
J= secateurs.
K= spade.
M= tridax.
N= elephant grass.
O= centrosema.
P= tropical kudzu.
Q= pieces of meat.
R= leather.
S=feather.
T= liver fluke.
U= tick.
V=water (to be label)
CHEMISTRY PRACTICAL SPECIMEN.
i. Red and Blue Litmus Paper
ii. Aqueous NH3
iii. Dilute HCl
iv. Barium Chloride Solution
vi. Dilute HNO3
vii. AgNO3
vii. Lime Water
APPARATUS.
*Glass rod
*Filtration paper *Spatula
*Two boiling tubes
*Four test tubes *Methyl Orange Indicator
*Wash Bottle containing distilled water [H2O] [-]2.8cm3 of concentrated H2SO4---An [-] 3?
9g of NaOH per dm3 of solution---Bn [-]6.6g of (NH4)2SO4 per dm3--- Cn [-] FeCl3 per dm3
CHEMISTRY PRACTICAL :: WHAT TO EXPECT.
QUESTION 1>> is always on titration. Guess by now you should know how to TABULATE your readings & AT THE SAME TIME, MANIPULATE YOUR READINGS TO GET YOUR END POINT.
[N.B :: Your teacher will give you an end point you will work on.]
PRACTICE HOW TO MANIPULATE YOUR TABLE.
Remember, this is key. IF YOUR SCHOOL'S END POINT is 23.30cm^3, YOU SHOULDN'T EXCEED or - 0.20. i.e IT'S A THING OF PLUS OR MINUS 0.20. IF YOUR SCHOOL'S END POINT IS 23.30, IT'S EITHER YOUR ANSWER IS 21.30, 24.30 or 25.30, 22.30. |
AND PLEASE NOTE: Your Volume of Pipette Used Should be noted on your answer sheet. Indicator Used should also be noted. To show how good you are, you can also decide to tell the examiner the SOLUTION IN BURETTE & also SOLUTION IN PIPETTE.(BEFORE THE TABLE) |
DON'T FORGET TO PUT THE UNITS OF ALL WHAT YOUR HAVE CALCULATED. ANY UNIT OMITTED ATTRACTS A DEDUCTION OF 1/2 (Half mark) | SO BE CAREFUL.
MAKE REFERENCE TO YOUR PAST QUESTION BOOKLET FOR MORE.
THAT'S ALL ON TITRATION.
TEST :: Cn Heat
OBSERVATION :: Gas evolved.
INFERENCE :: NH3 form NH4 salt present.
TEST :: Cn HCl BaCl
OBSERVATION :: White precipitate formed. *Insoluble in excess dilute HCl
INFERENCE :: SO4^2-, SO3^2-, CO3^2- suspected. *SO4^2- present. |
TEST :: Dn NaOH
OBSERVATION:: Reddish Brown Precipitate formed. Insoluble in excess.
INFERENCE :: Fe3 present. |
TEST :: Dn aqueous NH3
OBSERVATION:: Reddish Brown...
BIOLOGY PRACTICAL SPECIMEN
SPECIMEN A: stem of cassava plant/sugar cane/ sweat potato
SPECIMEN B: plantain/banana/pineapple sucker
SPECIMEN C: runner of grass
SPECIMEN D: spyrogyra spirament in water
SPECIMEN E: lung of a fresh killed goat
SPECIMEN F: freshly preserved toad
SPECIMEN G1: water leaf plant and fresh stem
SPECIMEN G2: skin of a goat/cow/sheep any one
SPECIMEN L: feather of a bird
SPECIMEN M: shell of a snail
SPECIMEN P: tuber of an irish potato
SPECIMEN Q: hibiscus
SPECIMEN R: cassava cutton
SPECIMEN S: Swind wing of cockroach.
I will check it out
ReplyDelete