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(1a)
NOTE THAT ^ MEANS Raise to
power.
PLS DRAW UR TABLE AS USUAL
AND INPUT THE
FOLLOWING:
Burette reading: final burette
reading(cm^3)
Initial burette reading (cm^3)
Volume of acid used(cm^3)
|Rough|:22.40,0.0 ,22.40,
|1st|:22.00,0.00,22.00
|2nd|:22.00,0.00,22.00
|3rd|:22.00,0.00,22.00
Average titre
value=22.00+22.00+22. 00/3
=22.00cm^3

(1biii) molar of
HCl=1+35.5=36.5g
Concentration of A in gdm^-3
=molar mass * concentration
in moldm^ -3
=36.5*0.209=7.63gdm^ -3

(1bi) 2.45=250cm root 3
Xg= 1000cm root 3
Xg = 1000x2.45/250 =2450/250
Xg = 9.8gdm^-3
Cb=conc. Of B in moldm^-3
Molar mass of
Na2CO3=23*2+12+3*16 = 106g
Cb= concentration in gdm^-3/
molar mass =9.8/106=0.09245
moldm^ -3
Concentration of B in moldm^3 =
0.0925 moldm -3.
(

(1bii)CAVA/CBVB = na/nb Where
ca= concentration of acid in
moldm^-3 Cb =concentration of
base in moldm^-3 VA= volume of
acid Vb= volume of base Na=no
of mole of acid Nb=no of mole of
base Ca= CB*VB*na/va * nb Ca =
0.0925*25*22.10*1 Ca=
4.625/22.10 = 0.209 moldm

(1biv) Na2CO3+2Hcl->2Nacl+H2O
+CO2
106g of Na2CO3 =1*22.4dm^-3
9.8g = xdm^3
:. xdm^-3=9.8*1*22.4/106
=219.52/106 = 2.071dm^-3

(1biv) Na2CO3+2Hcl->2Nacl+H2O
+CO2 106g of Na2CO3
=1*22.4dm^-3 9.8g = xdm^3 :.
xdm^-3=9.8*1*22.4/106
=219.52/106 = 2.071dm^-3

(3)
(i ) P is delivery tube
Q is drying tower
R is quick lime
S is dry ammonia
T is retort stand
(ii)By upward delivery
(iii)It serves as a drying agent
(iv)Ca(OH)2(s)+2NH4(s)-
>CaCl2+2H2O(l)+2NH3(g)

(2ai) |Test|: solution of C+ drops
of AgNO3(aq)+HNO3(aq)
+excess NH3(aq)
|Observation| white precipitate
occur in drops. The
precipitate dissolved in excess
NH3(aq)
|Inference| Cl power- present,
Cl^-1 confirmed.

(2a)
PLS DRAW A TABLE WITH, |TEST| |
OBSERVATION| |
INFERENCE| AND PUT THE
FOLLOWING:
|Test |: C+10cm power3 distilled water
|Observation|: C dissclved in
water to give a clear solution |
Inference|:soluble salts present

(2aiv)
|TEST|: Solution of C+NH3(aq) in
drops and then in exess |
OBSERVATION|: White precipitate
occur which disssolve
in excess.
|INFERENCE|: (Zn)^2+ confirmed







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Posted By DUBAI4YOU On 07:34 Wed, 09 Apr 2014

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