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(No3i)
Take 2cm^3 of each of the solutions to three different test tubes.
Then add NaoH in drops and then in excess to each.Any of the solution that forms White ppt indrops of NaoH and dissolves in excess zinc chloride, the solution that Will evolve a pungent smelling gas is ammonium trioxocarbonate while the solution that will form white ppt in drops of NaoH and persist in excess calcium trioxonitrate.
(3ii)
(1)liquid substance=Boiling point method
(2)Solid substance =melting point method
(bi)
(1)Boiling occurs at a specific temperature while evaporation occurs at all temperature
(2)Boiling takes place in entire liquid while evaporation takes place on the surface of the liquid
(bii) Because carbon(iv)oxide does not support combustion
(Ci)A molar solution is a solution that contains one mole of a solution in 1dm^3 of solution.
(Cii)indicator
(Ciii)methyl orange and phenolpthalein
(No3ai)
Take 2cm^3 of each of the solutions to three different test tubes. Then add NaoH in drops and then in excess to each.Any of the solution that forms White ppt indrops of NaoH and dissolves in excess zinc chloride, the solution that Will evolve a pungent smelling gas is ammonium trioxocarbonate while the solution that will form white ppt in drops of NaoH and persist in excess calcium trioxonitrate.
(3aii)
(1)liquid substance=Boiling point method
(2)Solid substance =melting point method
(3bi)
(1)Boiling occurs at a specific temperature while evaporation occurs at all temperature
(2)Boiling takes place in entire liquid while evaporation takes place on the surface of the liquid
(3bii) Because carbon(iv)oxide does not support combustion
(3Ci)A molar solution is a solution that contains one mole of a solution in 1dm^3 of solution.
(3Cii)indicator
(3Ciii)methyl orange and phenolpthalein
Ai) Observation: C dissolves in water to form a colourless solution.
Inference : C is a soluble salt.
Aii) observation : white precipitate formed.
Inference :CO3^2-, SO3^2- , SO4^2- or s^2- are suspected.
Aiii) observation : white ppt dissolved
Inference: CO3^2- present.
Bi) observation: effervescence occurred followed by evolution of a colourless and odourless gas which turns lime water milky.
Inference: gas is CO2 CO3^2- or HCO3^- present.
Bii) Observation: colourless solution turns to purple then to pink.
Inference:CO3^2- confirmed.
2Ai) Observation: C dissolves in water to form a colourless solution.
Inference : C is a soluble salt.
Aii) observation : white precipitate formed.
Inference :CO3^2-, SO3^2- , SO4^2- or s^2- are suspected.
Aiii) observation : white ppt dissolved
Inference: CO3^2- present.
[06-06, 10:54 AM] Chidera: No1)
The volume of pipette used = 25.00cm3
Titration/rough/1/2/3/
final burette reading(cm3)/ 16.20/ 16.10/ 25.90/ 16.00
Initial burette / 0.00/ 0.00/ 10.00/ 0.00
Volume of A used (cm3)/ 16.20 / 16.10 / 15 90 / 16.00
(a) i) Average volume of A used = (16.10 + 15.90 + 16.00/3) cm3 = (48.00/3) cm3 = 16cm3
ii) Equation for the reaction 2Hcl + Nacl - 2Nacl + C02 + H20
Bi) concentration of B in moldm^3
Concentration of A = CA = 0.1 moldm^3
Concentration of B = CB = ?
Volume of A = VA = 16.00cm3
Volume of B = VB = 25.00cm3
Number of moles of A = NA = 2.00moles
Number of moles of B = NB = 1.00moles
Using CAVA/CBVB = NA/NB
= CAVANB = CBVBNA
= CB = CAVANB/VBNA
CB = 0.1x 16.00 x 1.00/25.00 x 2.00
CB = 1.6 / 50.00 =0.032moldm-3
Concentration of B in moldm^-3 = 0.032moldm^-3
ii) Solubility of B in moldm^3
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