(1ai)
(i)graphite
(ii)diamond
(1aii)
(i)animal charcoal
(ii)carbon black
(1aiii)
(i)The property of elements are a periodic function of their atomic number
(ii)Elements are arranged in the periodic table according to the order of increasing in their atomic weight.
(1bi)
Periodicity can be defined as the trend or recurring variation in element properties with increasing atomic number.
(1bii)
using; mole = no; of atoms/avogadro's constant
0.5=no; of atoms/6.023*10²³
no; of atoms = 0.5*6.02*10²³=3.012*10²³atom
(1ci)
Faraday's first law of electrolysis state that the chemical deposition due to the flow of current through an electrolyte is directly proportional to the quantity of electricity (coulombs) passed through it.
(1cii)
2O²^- + 9^e --->2O²
no; of electron = 4
Q=20300C
G.M.V =22.4dm³.
F=96500C
Mole=Q/n,f
Mole=20300/4*96500
Mole=20300/386000
Mole=0.05mol
Recall; =vol/G.M.V
0.05=vol/22.4
vol=0.05*22.4
vol=1.12dm³
(1di)
Using H²SO⁴
H+ SO⁴^-¹
H+ OH^-
A+ Anode
OH ----> OH + e^-
2OH+(aq)+2OH(aq)---->2H²O(s)+O²(aq)
(1dii)
Tabulate
-Electrolyte- (I)teraoxosulphate(iv)acid
(II)Ester
-non electrolyte-
(III)phenol
(1ei)
(i)mercury
(1eii)
(I)no; of electron in Y =16
(II)no; of mass number =16+18=34
(III)sulphur
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2ai)
oxidation is a process involving a loss of electron(s), Reduction is a process in which an electronagetive element loses electron while an electropositive element gains electron.
2aii)
i)nitrogen is colourless,ordourless and testsless gas
ii)it is slightly soluble in water
2aiii)
x is (NH2)2 CO
y is H20
2bi)
i)element-chlorine
E/configuration=1s^2, 2s^2, 2p^6 3s^2, 3p^5 atomic number is 9
ii)NaOH=(23*1+16*1+1*1)
=23+16+1=40g
avogrado's constant=6.02*10^23
5g=5/40*6.02*10^23
=6.02*10^23=0.753*10^23
=7.53*10^22moles
iii)fractional abundance
=1/3 and 2/3
=1/3 * 18 + 2/3 * 20
=18/3+40/3=58/3
=19.33g
2ci)
faraday's second law of electrolysis states “When the same quantity of electricity is passed through different electrolytes, the masses of different ions liberated at the electrodes are directly proportional to their chemical equivalents (Equivalent weights).
2cii)
the single line represents one electron while double bonds represent two electrons
2ciii)
polymerization is any process in which relatively small molecules, called monomers, combine chemically to produce a very large chainlike or network molecule, called a polymer.
2civ)
i)it is used for making wine,beer,etc
ii)it is used as fuel
iii)it is used as preservative and steriling liquids
iv)it used for making anti-freeze reagents in automobile radiators
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6ai)
I)solution A is starch solution, sample B is Iodine
II)the colouration is formed due to the formation of an Iodine starch complex
III)
i)Iodine is used in treatment of goitre
ii)Iodine is used in making dye for colour photography
6aii)
dalton's law of partial pressure states that in a mixture of non-reacting gases, the total pressureexerted is equal to the sum of the partial pressuresof the individual gases.
6bi)
C - 4.08/12, H - 0.68/1, O - 5.46/16
0.34/0.34, 0.68/034, 0.34/0.34
1, 2, 1.
The emperical formula is CH2O
6bii)
( CH2O)n =60
((12*1)+(1*2)+(16*1))n=60
(12+2+16)n=60
30n/30=60/30
n=2
(CH2O)2=C2H4O2
the molecular formular is C2H202
6ci)
i)exothermic reaction
ii)A is activation energy, B is DH(Negative)
6cii)
i)removeal of carbon(iv)oxide
ii)liquetying the air
6ciii)
vander waal forces
6di)
fats have higher melting point than oil because fats are more denser
6dii)
i)it is poisonous
ii)it is 2,5 times denser than air
iii)it is greenish-yellow gas with a choking smell
6diii)
Zn^2+ has comppletely filled d-orbitals and there are no vacant d-orbitals for the transition of electrons while Sc^3+ has completely empty d-orbital and there are no electrons for d-d transition thus they are colourless
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