Member

merrylarry

Re- waec may/June assistance

(Apr 20 2015 at 11:41am)

welcum

Member

merrylarry

Re- waec may/June assistance

(Apr 20 2015 at 02:15pm)

1a)
Esterification is the reaction
between organic
acid e.g ethanoic acid and organic base
e.g
ethanol to produce salt e.g alkanoate and
water
(1b) -Low melting point
-Low thermal capacity
(1b)
Duralumin consist of aluminium,magnesium
and manganese
(1d)
-Raw materials is the chemical or
physical
materials in its natural or uncombined form
-Primary product is the useful product
during
chemical reactions
(1e)
Charles law states the volume of a fixed mass
of a gas is directly proportional to the
temperature provided pressure remains
constant
(1f)
-Eye shades -Laaboratory coats
-Hand gloves
-Spatula
(1g)
-Ammonia is used as a refrigerant in
refrigerators -Ammonia is used in production of
amine and
amide
(1h)
-Cr@cking
-Sodium Ethanoate -
(1i)
H2S04=0
(1*2)+S+(-2)4=0
2+S-8=0
S-6=0 S=6
(1j)
-Sodium trioxochlorate(v)
-Copper(ii)tetraoxosulphate
pentahydrate

Member

merrylarry

Re- waec may/June assistance

(Apr 20 2015 at 02:50pm)

2a)
i)
-J
-Q,X,Y
-X
-Q ii)
Ionic bond
iii) Number of neutrons in Q
iv)
X(^+) + R(^-2) -> X2R
v) R
vi)
Y
2b)
I)
i) The atomic orbitals are the group of
orbitals such as S-orbitals and D-orbitals
for filling electrons
ii)
-Atoms are made up of small indivisible
particles -Atoms of the same elements are
chemically alike and different from
atoms of different element
-When atoms combine together they
do so in simple ratio
II) It does not obey the law of
radioactivity (copied from 9jahub.com)
iii)
It contains protons,neutrons and
electrons
2c) i)
C(s)+O2(g)->CO2(g)
Volume of carbon
1/(30*60)*0.50=V/22.4
Volume of carbon =(0.50 *22.4)/(30*60)
=(6.2*10^-3)/44dm^3 =1.4*10^-4dm^3
ii)
mole of oxygen=(1.4*10^-4)/22.4
=6.3*10^-6dm^3

Member

merrylarry

Re- waec may/June assistance

(Apr 20 2015 at 02:53pm)

5a)
(i)-hydrogen chloride
(ii)-They are soluble in water
(iii)-They are less dense than air
(5b)
(i) -Solubility is the amount of solute of moles in
which can dissolve in 1dm^3 of solvent
at
standard temperature and pressure
-Sateurated solution is the solution in
which contains more solute than it can
dissolve at a
particular temperature
(ii)
-Temperature -Surface area of solid
(iii) Given; mass of Z=10.2g
Volume(V)=15.4cm^3
Temperature=40degreesC
Molar mass of Z=331
Mole=10.2g/331gmol
Solubility=Mole/Volume =0.031/(15.4*1000)
=2*10^-6mol/dm^3
(5c)
(i) - P is Ca^2a+,Calcium ion
Q is magnesium ion
Ca^(2a+)+H2(^+) + O2(^2-)->Ca(OH)2 (ii)
To the unknown substance in the
container,add copper(II)tetraoxosu­
lphate(IV)solution,
If a blue
precipitate is formed.This confirms the presence
of water
(iii) -Furring of kettle and boiler
-Stalagmite and Stalactite
(iv)
Na2SO4 + Ca(OH)2->CaSO4 + NaOH

Member

merrylarry

Re- waec may/June assistance

(Apr 20 2015 at 03:48pm)

CHEM Obj.
1-10 ADCDCCDDDB
11-20 DCABCDBCAA
21-30 BACCBCBDCD
31-40 DBDDBBCCBC
41-50 DCCDCCADAA

Member

bigDoc

Re- waec may/June assistance

(Apr 21 2015 at 06:04am)

Sorry about yesterday guys and thank God for merry! Thanks man for covering me

Member

merrylarry

Re- waec may/June assistance

(Apr 21 2015 at 09:43am)

financial accounting answers (1a)
(i)Bank statement: This can be defined
as the book which the bank prepares
showing the transactions between it
and the customer (ii)Bank reconciliation statement: This
can be defined as a (copied from
9jahub.com)statement that is prepared
to reconcile the disagreement of the
cash book and that of the bank
statement (1b)
-Uncredited cheque: There are cheques
received and entered on the debit side
of the cash book but have not been
entered in the bank statement due to
lateness or the bank statement had been prepared before the cheques
were paid in (copied from 9jahub.com) -Dividend;This is part of the profit for
shares held by the customers paid
directly into his bank account