WAEC 2019 CHEMISTRY OBJ AND ESSAY VERIFIED ANSWER |        

logo






UPDATES!!
star Click Here To View 2020 Waec Timetable Now - Is Out
star Waec Exam Runz/How to get your Waec Answer Click here
star Neco Exam Expo/How to Pass Neco Exam Click here
star Nabteb Exam Answer/Pass Nabteb Exam Click here

UPDATE: FG Approved All Exam Class to Resume School on 4th August and Waec Exam start August 17th! (Invite Your Classmates,Friends Here)



« | »

WAEC 2019 CHEMISTRY OBJ AND ESSAY VERIFIED ANSWER

Chem-Obj
1DAABADACBD
11AABCACDADD
21CCABBDDBAA
31AABDBCDBCB
41BACBCCBDDD
(1a)
– High temperature of 4500degree(c) or more
– High pressure
– Catalyst
(1b)
– For decoration
– For protection
(1c)
Calcium oxide (Cao) is alkaline and Hcl is acidic. The two react to form calcium chloride and water; instead of dry Hcl after that, it will end up with wet calcium chloride
(1d)
This is an oxidation reaction. The acid oxidizes the iron (II) sulphate to iron (III). The baron gas evolved is Nitrogen (IV) oxide
(1ei)
(i) Zinc oxide with H2SO4
ZnO(s) + H2SO4 —> ZnSO4(aq) + H2O(l)
(ii) Zinc oxide with sodium hydroxide solutions
ZnO(s) + 2NaOH(aq) —> Na2ZnO(aq) + H2O(l)
(1eii)
Amphoteric property
(1f)
(i) Have the same atomic number
(ii) Have different mass numbers
(1g)
– Hcl
-O2
(1h)
(i) H2S
(ii) SO2

(1k)
Carbon-12 scale is the standard from which atomic masses of all nuclei’s are measured. It is used to ascertain one mole of a substance as the amount of substance which contains as many elementary entities as there are atoms in 12grams of carbon-12
(1j)
– The concentration of the resistants and products are equal
– The rate of the forward reaction is same as the rate of the backward reaction
===========================
2) CLICK HERE TO VIEW IMAGE
(2ai)
C10H22—–>(cracking)—->C6H14 + C4H8
P is C4H8
(2aii)
H H H H
| | | |
H-C=C-C-C-H
| |
H H

H CH3 H
| | |
H-C= C- C-H
|
H
(2aiii)
P would be polymerized because it contain double bond
(2b)
Hundi’s rule:Electrons occupy each orbital singly first before pairing takes place in a degenerated orbital
Aufbau’s principle:Electrons enter into orbitals in order of increasing energy

CHECK OUT:  2020/2021 Geography Syllabus from JAMB

(2ci)
– NaH —> ionic
– H2 –> Covalent
– H2S –> Covalent
– NH4Cl — Vander waals

(2cii)
– NaH —> soluble (dissolve)
– H2 –> Insoluble
– H2S –> Moderately soluble
– NH4Cl — soluble

(2ciii)
– H2S(g) + H2O(l) —> H3O^+(aq) + HS(aq)
– HS(aq) + H2O(l) —> H3O^+(aq) + S^2-(aq)

(2d)
(i)Number of unpaired electrons=zero
(ii)J would be a good reducing agent
(iii)It is found in group 2.It is a metal.Metals are good reducing agent

(5ai)
DRAW THE DIAGRAM
(5aii)
(i)It is used in the sterilization of water for domestic and industrial use and in the treatment of sewage
(ii)It is used as a bleaching agent for cotton linen and wood-pulp
(5b)
Preparation of hydrogen from water gas:
This is called Bosch process: In this process large quantities of hydrogen are produced from cheap raw materials namely water and coke when steam is passed over red hot coke (carbon) at about 1200C, a mixture of carbon(II) oxide and hydrogen ion and water gas is produced .Excess steam is then mixed with the water gas and passed over a catalyst iron(III)oxide at 450C.As a result the carbon(II)oxide in the water gas is converted by CO2 with a further yield of hydrogen
Endothermic reaction
H2O(g) + C(s)—> CO(g)
(5ci)
The chief ore of aluminium is bauxite
(5cii)
The ore of aluminium is purified by electrolysis to remove the impurities present
(5ciii)
Carbon or platinum electrodes
(5civ)
Cryolite is added to remove the impurities present
(5d)
Coal, coal tar, ammoniacal liquor

CHECK OUT:  WAEC 2020/2021 SPECIMEN FOR ALL SCIENCE SUBJECTS AND SOLUTIONS

 

ceebook,
wakagist,
expotab,
gurusloaded waec 2019,
gurusloaded waec expo 2019,
www.examloaded.com 2019,
naija expo exam site,https://examgreat.net/,
WITH EXAMGREAT YOUR SUCCESS IS 100% SURE, WE ARE READY FOR … waec gce 2020, gce time table runz, examorigin.com.ng, examgreat.net, exam great.com, examgreat.com.ng, funloaded.com.ng, funloaded.net, funloaded jamb source, funloaded waec source, funloaded neco source, donprosper jamb runs, donprosper waec runs, 2020 english expo, jamb 2020 similar questions, jamb 2020 syllabus, 2020 jamb answer source, instagram log in, Exambest – JAMB Answers GCE Answers NECO Answers and WAEC,
https://www.facebook.com, › Other › News & Media Website
@exambest.net,Exambest – JAMB Answers GCE Answers NECO Answers and WAEC Answers, funloaded 2020 waec neco jamb cbt exam runs, Examloaded – Get Answer To All Exam Questions JAMB|WAEC and neco runs/runz, examloaded.com source,
jamb Specialize on Jamb Waec Neco Gce, Exam Questions and Answers 2020 runs for jamb , Syllabus, Expo, Pre-Degree, University, Post-Utme, Postgraduate, Admission, Funloaded – Your #1 Legit Source For Nigeria Universities …
funloaded.org.ng
Your #1 Legit Source For Nigeria Universities, Polytechnics and Colleges: Admission Screenings, Admission List, JAMB Expo, Post-UTME Expo, A’LEVEL Expo, Top 20 Nigeria Education Blogs, FunLoaded.com Official – Home | Facebook, FunLoaded.com Official
Official Exam Expo Center + Free Browsing And Unlimited Downloads. … Jamb CBT Expo, Weac, Neco & Gce Runz/Expo. … Real Exam Expo/Runz For All Your Examwaec,neco,jamb&nabteb 100%Answer,

Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Categories: Jamb answer expo exam, Waec runs 2020 expo answer supply


SELECT EXAM YOU WILL WRITE AND CLICK ON IT
*INVITE YOUR FRIENDS TO OUR WEBSITE*

0 Responses

Leave a Reply

« | »




Recent Posts


Pages



Open chat
1
Chat Admin Now
Hello
Chat Us For Exam Expo