Past 2017 top best forum
Today's Date
Nigeria free 2018 Gallery
9ja NOTICE: You are currently viewing this website as a Guest and are restricted from viewing some vital information. For more permissions on Earlyface.com.ng? Like posting Comments, Topics and Uploading contents without Verification And Moderator's approval. Fast loading and quick accessibility. Registration is required. Please Login or Register now to gain full access. It is fast and free!!

CLICK HERE NOW TO BECOME EARLYFACE MEMBER...


Author Topic: Neco practical biology answer 2021/2022  (Read 682 times)

0 Members and 1 Guest are viewing this topic.

Offline NORTOLA

  • VIP MEMBER
  • Teacher Member
  • *
  • Posts: 233
  • Vote for me: +39/-8
  • Location: Akwa ibom state
Re: Neco practical biology answer 2021/2022
« on: July 28, 2021, 08:51:04 am »
COMPLETED


Completed
CHEMISTRY-OBJ
1EECBBAEBBB
11DDDBEAEABB
21DBECCDAAAB
31BADCBACDAC
41CECCEADBDC
51CEBEEDDBAE
Completed!.
====================================
CHEMISTRY-THEORY
(1ai)
(i) Base has bitter taste
(ii) Base is soapy to touch
(iii) Base turns litmus paper blue

(1aii)
The steps involved are:
(i)Shift conversion
(ii)Removal of carbon (iv) oxide
(iii)Steam reforming

(1aiii)
Cracking is the process by which heavier hydrocarbon molecule is splitted into two or more lighter molecules

(1aiv)
Thermal cracking

(1bi)
P ion = 1s²2s²2p⁶

(1bii)
Formula of chloride is Pcl2

(1biii)
Reducing agent
This is because it undergoes oxidation by losing electrons

(1ci)
Electron affinity is the energy released when a gaseous atom gains an electron to form a gaseous negative ion.

(1cii)
This is because it has lone pairs of electrons

(1di)
(i) By adding a catalyst

(ii) FeS(s) + 2HCl(g) -----> FeCl(g) + H2S(s)

Xg = ?
No. of FeCl2 = 127g/mole
No. of FeS= 88g/mole

Mole = Mass/ No. of Mass = 3.2/127 = 0.025mole of FeCl2

By comparison,
1 mole of FeS = 1 mole of FeCl2
X moles of FeS = 0.025 of FeCl2
X = 0.025mole of FeS

Recall,
Mass = Mole * molar mass
Mass = 0.025*88
Mass = 2.2g of FeS
X = 2.2g

(1dii)
(i)Chlorofluorocarbons
(ii)Ammonia
°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°′°°°°°°°°°°°°°°
(4a)
(i)Enthalpy of combustion can be defined as the amount of heat evolved when one mole of a substance burns in air or oxygen

(ii) Isomerism can be defined as a phenomenon in which organic compounds are having the same molecular formula but different structural formula

(4bi)
NO2 - Acidic oxide
CO - Neutral oxide
Fe2O3 - Basic oxide
Al2O3 - Amphoteric oxide

(4bii)
(i)Nitrous oxide
(ii)Carbon (iv) oxide

(4c)
(i) Fractional distillation of liquid air

(ii) 2KNO3 -----> 2KNO2(s) + O2(g)

(NH)CO3(s) ------>2NH3(g) + CO2(g) + H2O(g)

(iii) No. of molecules = 4/16 × 6.02 × 10²³
= 1.5 × 10²³

(4di)
(i)Sodium
(ii)Potassium

(4dii)
(i)Carbon (iv) oxide
(ii)Carbon

(4diii)
(i)Hydration
(ii)Oxidation
°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°°′°°°°°°°°°°°°°°

(3a)
(i) Iron (Fe)
(ii) Fe3C4
(iii)
- chlorine displace bromine
- The displaced bromine gives the reddish brown colour
(iv) 2KBr(aq) + Cl2(g) ----> 2KCl(aq) + Br2(l)

(3b)
(i)
- Cement industries
- Glass industries
(ii) Quick lime
(iii) TABULATE PLS
=>Salt to be prepared<=
- KNO3
- CaCl2
- FeCl3
- CuSO4
- PbSO4

=>Starting material<=
- KOH
- CaCO3
- Fe(s)
- CuO
- Pb(NO3)2

=>Method of preparation<=
- Neutralization
- Dilute acid and trioxocarbonate (iv)
- Combination of constituent elements
- Dilute acid and insoluble base
- Double decomposition

(3c)
(i) By burning sulphur in dry air
(ii) 2SO2(aq) + O2(g) ------> 2SO3(aq) + heat

(iii)
- Combining sulphur (iv) oxide with oxygen in excess to firm sulphur (vi) oxide
- Cooling and passing the SO3 formed through and absorption tower to produce the acid

(d)
(i) 2*9600C produces 119g
(1.5*2*3600)C produces xg
x= 1.5*2*3600*119/2*96500
x= 6.66grams

(ii) Strong electrolyte conducts large currents WHILE Weak electrolyte do not conduct electricity readily
====================================

(6ai)
Diagram


(6aii)
Vanadium (v) oxide : It enables equilibrium equilibrium to be reached in a shorter time

(6b)
(i) Caustic soda solution
(ii) Pure Alumina in molten cryolite
(iii) Graphite rods: Oxygen is given off at the anode, slowing burning away the anode as CO2

(6c)
(i)
- Dilute acids have a sour taste
- Acids turn blue litmus red
- Concentrated forms of strong acids are corrosive

(ii) HCl will have a larger electrical conductivity because it ionizes completely in water to give hydrogen ions with concentration very high

(iii)
(i) As an acid with bases
NaCl(aq) + HNO3(aq) ---> NaNO3(aq) + H2O(l)

(ii) H2S(g) + 2HNO3(aq) ----> S(s) + 2H2O(l) + 2NO2(g)
Completed
°°°°°°°°°°°°°°°°°°°°°

 

Related Topics

  Subject / Started by Replies Last post
0 Replies
245 Views
Last post November 13, 2018, 08:27:54 am
by JEFFREY96
2 Replies
684 Views
Last post July 11, 2021, 09:17:20 pm
by Kalu Joseph
5 Replies
643 Views
Last post July 28, 2021, 10:45:03 pm
by batulla
0 Replies
631 Views
Last post July 14, 2021, 09:31:18 am
by NORTOLA
3 Replies
813 Views
Last post August 05, 2021, 08:46:14 am
by bismarckmc
3 Replies
897 Views
Last post September 17, 2021, 10:28:08 am
by NORTOLA
3 Replies
331 Views
Last post July 19, 2022, 11:03:25 am
by MANDINHO

Updated Topics

NetContacts Membership Invitation by wedco893
March 26, 2024, 06:42:58 pm

NetContacts Membership Invitation by wedco893
March 26, 2024, 06:26:58 pm

CORRECT: 2024/2025 JAMB RUNS SUBSCRIPTION( REFORMED PACKAGES) by MANDINHO
March 24, 2024, 09:11:15 pm

UK FOOTBALL POOLS COUPON | 30TH MARCH 2024 | WEEK 39: X-02-X by wedco893
March 24, 2024, 07:40:25 pm

UK FOOTBALL POOLS COUPON | 23RD MARCH 2024 | WEEK 38: X-05-X by wedco893
March 18, 2024, 06:52:10 pm

Solve you've been logout for using unofficial Whatsapp app Gb Whatsapp problem by Wiz.gee
March 16, 2024, 02:18:51 am

Girls: Female's Education Ends In Kitchen by Babatunde aliyat
March 12, 2024, 06:12:54 am


FBLike US on Facebook.. TWFollow US on Twitter..

Portal
Forum
RSS Feeds
FAQ
Members Intro
Announcements
Privacy Policy
Terms Of Use
Partners
About Us

Problem Solutions
Global News
Sports
Celebs
Politics
Gists In Town
General
Song Lyrics
Dating
Religion

Examination
Post-UTME/Admission
School News
Online Reading
Scholarship
Education
Entertainment
Download Links
Stories
Fashion

MTN NG
9Mobile NG
Airtel NG
Glo NG
World Networks
Pc Tweaks
Mobile Phone
Computer Tips
WebMaster
Programming

Browsing Cheats
Net Tricks
Health n Welfare
Latest Jobs
EarlyFace Group Of Nigeria © 2022