Unlimitedapps
1ai)
A mixture contains two or more constituents which can
easily be seperated by physical methods
1aii )
magnesium trioxonitrate ( v ) = Mg ( NO3 ) 2
molar mass of Mg ( NO 3) 2
=( 1* 24) + 2 ( 14* 1 + 16* 3)
=24 + 2 ( 14 + 48 )
=24 + 28 + 96 = 148 g/mol
% of nitrogen = 2 *24 *100 /148
% of nitrogen = 48 *100 /148
% of nitrogen = 4800 /148
% of nitrogen = 32 . 43 %
1aiii )
i ) calcium oxide ( CaO)
ii ) calcium choride ( CaCl 2)
1bi)
CnH2n +1OH
1bii )
hydrolysation
1biii )
i ) displacement reaction
ii ) double decomposition reaction
iii ) decomposition reaction
iv ) catalytic reaction
v ) reversible reaction
1biv )
i ) endothermic heat change
ii ) exothermic heat change
1ci)
i ) methyl orange
ii ) phenolphthalein
iii ) litmus
1cii )
NH 4Cl +Ca( OH ) 2- --- -> CaCl 2+2NH 3+2 H2O
1ciii )
it is collected by upward delivery
1civ )
mass of gas = 1. 58 *22 . 4 = 35 . 392
vapour density = 35 . 392 /1
relative molecular mass= V . D * 2
=35. 392* 2
relative molecular mass= 70. 784
++++ +++++ +++++ +++++ +++
5ai)
i ) carbon monoxide and hydrogen
ii ) carbon monoxide , carbon dioxide, hydrogen and nitrogen
5aii )
i ) colloids is an intermediate between true solution and a
suspension
ii ) condensation is the process by which water vapour in the
air is changed to liquid water
5bi)
CaC 03 +2HCl-- -- -> CaCl 2 +H2O +CO2
5bii )
i ) it is used in fire extinguishers
ii ) it is used in the manufacturing of mineral water
iii ) carbon( iv ) oxide is used as a coolant in nuclear reactors
5biii )
i ) Cr 2O 7^-2
=2Cr + C - 2* 7) = -2
2Cr - 14 = - 2
2Cr = -2 + 14
2Cr /2 = 12/2
Cr = 6
ii ) Cr 2{ SO 4} 3
2Cr + 3 ( - 2* 1 + -2* 4) = 0
2Cr + 3 ( - 2 - 8 ) = 0
2Cr + 3 ( - 10) = 0
2Cr - 30 = 0
2Cr /2 = 30/2
Cr = 15
5ci)
vulcanization is a chemical process of converting netural
rubber or related polymers into more durable materials
through the addition of sulphur or other equivalent curatives
or accelerators
5cii )
Time Taken ( t ) for 6. 35g of copper ( ii ) tetraoxosulphate
solution
Cu^2^+ + 2c -- -- --- > Cu
Q = 2* 63. 5* 95600
Q = 12255500
Q = 1t
12255500/10 = 10 *t /10
t = 1225550 /60 = 204258 . 3
5ciii ) loading . . . .
++++ +++++ +++++ +++++ +++
4ai)
electrolytic cell is a cell that consist of a container of
electrolyte with two electrodes connected to a suitable
direct current supply
4aii )
i ) daniel cell
ii ) Leclanché cell
4aiii )
i ) copper
ii ) tin
4aiv )
action of dilute acide on zinc
4av )
Zn +2HCl- --- -- > ZnCl+ H2
4bi)
i ) dinitrogen ( i ) oxide( N2O )
ii ) nitrogen ( v ) oxide( N 2O5 )
iii ) nitrogen ( iv ) oxide( NO 2)
4bii )
charle' s law states that the volume of a fixed mass of gas
varies directly with the absolute ( kelvin ) temperature provided
the pressure remains constant .
4biii )
P 1 V 1 = P 2 V 2
given that
P 1 = 900 mmHg
P 2 = 750 mmHg
V 1 = 300 cm ^3
V 2 = ?
V 2 = P 1V 1 /P 2
V 2 = 900 * 300/750
V 2 = 270000 /750
V 2 = 360 cm ^3
4biv )
% composition carbon
= 12 /( 12* 6) + ( 1* 6) * 100 %
= 12 /72+6 * 100
= 12 /78 * 100% = 1200/78 %
%composition of carbon = 15. 38%
4c)
TABULATE
-THERMOPLASTS-
i ) it melts when heat is applied to it
ii ) highly recycled
-THERMOSETS -
i ) does not melt when heat is applied
ii ) cannot be recycled
++++ +++++ +++++ +++++ +++
2ai)
ionization energy deals with electron loss while electron loss
while electron afinity deals with electron gain
2aii )
i ) they are used to dry gases
ii ) they are used to recover valuable vapours from industrial
effluents and refine petroleum
2bi)
TABULATE
-RHOMBIC SULPHUR-
i ) bright yellow in colour
ii ) it is octohedral in shape
-MONOCLINIC SULPHUR-
i ) amber in colour
ii ) it is needle like in shape
2bii )
oxygen = 60%
sodium = 40 %
oxygen 60 /16
3. 75 /1. 74 = 2
sodium 40/23
1. 74 /1. 74 = 1
the emperical formula is NaO 2
2biii )
sodium( iv ) oxide
2ci)
i ) x is hydrophobic region
ii ) y is hydrophilic religion
2cii )
i ) for laundry purpose
ii ) for fuel
2ciii )
i ) the distance of outermost electron from the nucleus
ii ) the size of the positive nuclear charge
iii ) the screening effect of inner electrons
2civ )
period law states that the properties of the elements are a
period function of their atomic number
2di)
n-- -pentane -- --- > n- --butane -- --- > 2- --methylbutane --- 2, 2-- -
dimethylpropane
2dii )
i ) glucose
ii ) galactose
+++++++++++++++++++++++++
(6ai)
-addition of water to calcium oxide
-rusting of iron in moist air
(6aii)
-Enhanced weathering
-Direct air capture
-Bio-energy with carbon capture & storage
(6aiii)
Enhanced weathering equation
CaCO3 + CO2 + H2O → Ca2+ + 2HCO3−
(6aiv)
Because it is an oxidizing agent
(6bi)
Physical properties of Ethene:
-It is neutral to litmus paper
-It is slightly less dense than air
Physical properties of Ethanol:
-It is readily soluble in water in all proportions
-Ethanol is a colourless, volatile liquid with a characteristic taste and smell
(6bii)
CH3CH2OH-------->CH3COOH
(6biii)
sp3-hybridized molecule.
(6biii)
sp3-hybridized molecule.
