Featured

    Important Posts

Search For Any Latest Schools News Below


WAEC 2016/2017 May/June Chemistry Objectives & Theory Answers Posted Here

CURRENT EXAMINATION:

WAEC Chemistry Questions & Answers ;
TO GET ANSWERS EARLIER CLICK ON THIS LINK AND LIKE OUR FACEBOOK PAGE

TO GET ANSWERS EARLIER CLICK ON THIS LINK AND FOLLOW US ON TWITTER PAGE 
CHEMISTRY OBJECTIVES
1CAACABCDBC
11BABAADBDCA
21BCCAABCDCB
31ABCBCCCBBC
41ABDBBBAABB

CHEMISTRY THEORY
1a)

nucleons is the collective name for two important sub-atomic particles:neutrons and protons

1b)

Graham's law of diffusion states that at a constant temperature and presure,the rate of diffusion of a gas is inversely proportional to the square root of it density

1c)

because when aluminum is exposed to moist air,a thin continuous coating of aluminum oxide is formed, which prevents futher attack of the aluminium by atmospheric oxygen and water or steam under normal conditions

1d)

i) electron - affinity

ii) electron - negativity

iii) ionization - energy

1e)

i) the molecule of real gases occupies space and there are forces of the attraction between them

ii) real gases do liquefy when their temperature droops.

1f)

i)used in seperation of different component of crude oil.

ii)it is used for separating acetonic from water

iii) it is used for obtaining different gases from air for industrial use.

1g)

i)concentration of ions in electrolyte

ii)the nature of the electrode

iii)the position of ions in the electrochemical series

1h)

i)substitution reaction

ii)addition reaction

1i)

i)carbon dioxide

ii)water vapour

iii) carbon monoxide

1j)

i)centrifugation

ii)sieving

iii)evaporation to dryness

2a)

i) isotopy

ii) they have the same number of proton (atomic number) but different mass number

iii) oxygen,carbon

iv)1s^2,2s^2,2p^6,3s^2,3p^5

2bi)

PHYSICAL PROPERTIES

METAL

i) high melting and boiling point

ii) they are good conductor of heat and electricity

NON-MATEL

i)they have lower melting and boiling point

ii)they are poor conductors of heat and electricity.



CHEMICAL PROPERTIES

METAL

i) they form basic and ampheric oxides

ii)the react by electron lose or donation of electron

NON-METAL

i)the form acidic oxides

ii)the react by sharing and accepting electrons

2bii)

i) Al2 O3(Aluminum oxide)

ii) sodium hydride (NaH)

iii)zinc trioxocarbonate(iv)ZnCo3

iv)silicon tetrachloride (SiCl4)

2ci)

i) variable oxidation states

ii) complex ion formation

iii) they possess strong metallic bonding

2cii)

1s^2,2s^2, 2p^6, 3s^2, 3p^6, 3d^10, 4s^2

2ciii)

Zinc is not considered as a typical transition element bacause it has only one oxidation state of +2, it metallic ion are not coloured and it is not used as a catalyst.

2d)

Na2Co3 + MgCl2 ---->2NaCl + MgCo3

1mole 1mole 2mole 1mole

molar mass of Na2 Co3 = 2 * 23 + 12 * 1 + 16 * 3 = 46+12+48 = 106g



3ai)
structral isomerism is the existance of two or more compounds ( known as isomers) with the same molecular formula but different molecular structures
3ai)
i) tertiary alkanol
ii) secondary alkanol
iii) primary alkanol
3bi)
i) 2[CH3 CH2 COOH ] 2K(s)---->
ii) [CH3 CH2 COO ] K + H2

i) 2[CH3 CH2 COOH ] +2 K(s) ------> 2[ CH3 CH2 COO ] K + H2
ii) CH3 CH2 COOH + C4 H9OH
HEAT---->CH3 CH2 COO C4 H9 + H20
H2SO4
iii)CH3 CH2 CH2 CH20H + H^+
KMnO4------> CH3 CH2 CH2 CH2 - 0H
EXCESS
3bii)
i) potassium ethanoate,hydrogen
ii) butyl propanoate and water
iii) enthanal
3c)
the percentage composition of the hydrocarbon
= 100
H + C = 100
14.3 + C =100
C= 100 - 14.3
C= 85.7%
================

3D. -----------------------------------

(4ai)
calcium chloride, CaCl2
(4aii)
to the unknown ssubstance in a gas jar, add
small quantity of lime water. if the gas is
carbon(iv)oxide, it turns lime water milky
while carbon (ii) oxide has no effect
(4bi)
oxygen is releasedf abundantly from air and
nitrogen is produced by the reaction of
potassium trioxonitrate(v) with concentrated
hydrochloric acid
(4bii)
oxygen gas rekindle a lighted splint while
nitrogen does not
(4ci)
Bauxite is preferred because it is readily
available in the earth crust
(4cii)
-trioxosilicate(iii)
-carbon(iv)oxide
(4ciii)
-it helps to purify the bauxite
(4civ)
it is difficult to extract aluminium by chemical
reduction of aluminium oxide in amphoteric
(4cv)
AL2O3+NaOH=>Na2O + Al+ H20

5ai)

Na2S2O3 ===>2 + 2x + 6 = 0

2x = 6 - 2 = 4

X = 4/2

X = 2

The oxidation number of sulphur is 2



5aii)

Rhombic&monoclinic



5aiii)

- Both are tetravalent

- both are allotrope of carbon



5bi)

CO2&Chloroflorocarbon



5bii)

There is increase in sun radiation reaching the earths surface ie Global warming



5biii)

ThunderStorm



5iv)

I2KNo3. -------->2KNO3 + O2

2AgNo3 --------->. 2Ag + 2No



5ci)

Calcium chloride in a solution can give rise to crystal using filteration&evaporation to dryness. The sol is filtered into filtrate&residue b4 evaporation to dryness takes place.



5cii)

- Because of presence of hydrogen bonding in NH3

- Because Iodine as higher molecular mass than chlorine



5di)

Mol of Nacl = Mass / MM

= 5.85/ 58.01

= 0.1mol

From the equation

2mol of Nacl gives 2mol of HCL, 0.1mol of Nacl gives 0.1mol of Hcl

Vol of Hcl = 0.1 x 22.4 = 2.24mol/dm^3
 
 
 


CALL OR TEXT MR CHINEKS ON 08107431933 TO SUBSCRIBE FOR WAEC Verified And Confirmed Chemistry Questions & Answers
NOTE: 
DIRECT MOBILE=N800
LINK(ONLINE ANS) = N400

SUBSCRIPTION ENDS 30 MINUTES BEFORE EXAM COMMENCES

Subscribe At Cheaper Rate By Clicking Here!!!
NOTE:

Online Answers comes 1hrs:30mins after the Commencement.

Also See: 2016/2017 WAEC Christain Religious Knowledge [C.R.K] & Islamic Religious Knowledge [IRK] Answers Posted Here [18/04/2016]

GOODLUCK!!!

👉2017 JAMB, WAEC, NECO, NABTEB Students Join Our Group For Latest Update Now

👉Like Us On Facebook Page Here

👉Follow Us On Twitter Here


Search For Any Latest Schools News Below

→Read Our Previous Post

→Read Our Next Post

→Essay Competition: ElitesplanetBlog 2016/2017 Essay Competition For [Secondary School Students]Begins
About Author: author Oscar Emmanuel Chineks is the founder and editor of ElitesplanetBlog. He loves to share education news from various sources to keep readers informed.Read More...

Join him on Google+ | Facebook | Twitter | Linkedin

Get Latest University, Polytechnics, Colleges, Admission News And Updates Straight To Your Email Daily
Enter your email address:


Delivered by FeedBurner

Post a Comment

We Appreciate And Welcome Comments... Please Try To Drop Your Comment Or Views For This Post....

Note : All Comments Are Moderated And No Spamming
Text/Whatsapp: +2348107431933.
Available Monday-Friday -10am-6Pm

  • Total Visits

    Copyright © University, Polytechnic, Colleges Admission And School News | Designed By MR CHINEKS