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WAEC GCE 2022 2ND SERIES CHEMISTRY PRACTICAL QUESTIONS AND ANSWERS

WAEC 2022 CHEMISTRY PRACTICAL QUESTIONS AND ANSWERS

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TAKE NOTE

For question 1

Use your school’s endpoint and use it wherever you see our endpoint (24.10cm³) …and calculate with it

Use the answer you got in 1b(i) to solve in 1b(ii) i.e we got 0.0482, as u can see, we used it in 1bii.

1a)
Volume of pipette used, VA = 25.0cm³
[TABULATE]
Burette Reading |  Rough titre | 1st titre | 2nd titre |
Final Burette reading (cm³) |  25.60 | 32.80 | 26.40
Initial Burette reading (cm³) | 1.20 | 8.70 | 2.30
Volume of Na₂S₂O₃ used | 24.40 | 24.10 | 24.10
Average burette reading = (24.10 + 24.10)/2
Average volume of Na₂S₂O₃ used = 24.10cm³
VB = 24.10cm³
(1bi)
Given: CB = 0.1mol/dm³
VB = 24.10cm³
VA = 25.0cm³
CA =?
From equation nA/nB = 1/2
.: Using (CABA)/CBVB = (nA)/nB
(CA x 25)/(0.1×24.10) = 1/2
CA = (0.1×24.10)/(25×2)
CA = 0.0482mol/dm³
.: Concentration of iodine in A = 0.0482mol/dm³
(1bii)
Mass in gramms of iodine in 1dm³ of A = Molarity × Molar mass of iodine
= 0.0482×127(2)
= 12.2428g/dm³
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(1)
(2a)
[TABULATE]
=TEST=
C + Distilled water
=OBSERVATION=
It dissolves completely to give a light green solution.
=INFERENCE=
Soluble salt.
(2ai)
=TEST=
Solution C + NaOH in drops and in excess + Heat gently
=OBSERVATION=
A dirty green precipitate is formed which remains insoluble in excess.
Effervescence occurs in which a colourless gas with a pungent smell which turns red litmus blue is given off.
=INFERENCE=
Fe²⁺ is present.
NH₃ gas form.
NH₄⁺ is present.
(2aii)
=TEST=
Solution + BaCl₂ + dilute HCL in excess
=OBSERVATION=
A white precipitate is formed.
The white precipitate remains insoluble and gives a white dense forms
=INFERENCE=
SO₄²⁻, CO₃²⁻, SO₃²⁻, is present.
SO₄²⁻ confirmed.
(2b)
Cations → Fe²⁺ and NH₄⁺
Anions → SO₄²⁻
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(2)
Questions 3 
(3a)
(3bi)
(I) H2 ; downward displacement of water
(II) NH3; downward displacement of air
(III) HCL; upward displacement of air
(3bii)
(I) Hydrogen gas(H2) is collected by the downward displacement of water because It is insoluble in water and It form an explosive mixture with air.
(II) Ammonia gas(NH3) is collected by downward displacement of air because it is lighter than air
(III) HCl gas is collected by upward displacement of air because it is 1.28 times heavier than air.
(3c)
(i) Distillation
(ii) Filtration followed by evaporation to dryness
(3d)
This is because KCl react with NaHCO₃ to form two salts
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1-10:DCADABCADB

11-20:ABDBABDAAA
21-30:ACBABBCBCB
31-40:ABDDDBDACA
41-50:ACCADCDBBA

Completed!
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(5a)

TABULATE

=EARTHWORM=

(i) Straight

(ii) Simple

(iii) It feeds on fluid

=COCKROACH=

(i) Curve

(ii) More enveloped

(iii) It feeds on both fluid and solid

(5aii)

(i)Possession of crop

(ii)Possession of gizzard

(iii)Possession of pharynx

(5b)

(i) Water cycle

(ii) – Plant contribute through transpiration

– Animals contribute through respiration

– Animals contribute through perspiration

(iii)

– X: Condensation

– Y: Transpiration

– Z: Evaporation

(5c)

TABULATE

=ORGAN=

(i) Kidney

(ii) Skin

=DISEASES=

(i) Kidney stones, diuresis and oedema

(ii) Eczema, acne, vitiligo

(5di)

This is a process whereby heterotrophic organisms utilize the remains of one living tissue as a source of nutrition

(5dii)

(i) Fungi

(ii) Bacteria

(5diii)

Temperature

(5div)

Carbon cycle

(5e)

They exhibit heterotrophic nutrition known as carnivorous or insectivorous feeding. They have attractive colours that attracts insects to them. Once the insect lands in their spine, they are killed and digested.

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(1ai) cell can be defined as the basic structural and functional unit of life. All living organism are made up of cells

(1aii)

(i) Robert Hooke

(ii) Felix Dujardin

(iii) Mathias Schleiden

(1bi)

 

(1bii)

Red blood cell

(1biii)

It does not replicate itself but rather die off

(1c)

(i) Nucleus

(ii) Cell membrane

(iii) Cytoplasm

(iv) Chloroplast

(v) Mitochondrion

(vi) Golgi body

(2a) Kindly follow the instructions by ticking ✅ it out

(2bi)

TABULATE

=HERBIVORE=

(i) Absence of canine

(ii) Presence of diastema

(iii) Weak molar

=CARNIVORE=

(i) Presence of canine

(ii) Absence of diastema

(iii) Strong molar

(2bii)

TABULATE

=HUMAN=

(i) Absence of diastema

(ii) Presence of canine

(iii) Presence of upper incisors

(iv) Presence of upper premolar

=GOAT=

(i) Presence of diastema

(ii) Absence of canine

(iii) Absence of upper incisors

(iv) Absence of upper premolar

(2c)

Milk teeth are the first set of teeth that grows in an infant when they want to start feeding on solid food. It starts to grow 6months after birth. There 20 milk teeth

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(4ai)

Conservation Law states that the amount of the conserved quantity at a point or within a volume can only change by the amount of the quantity which flows in or out of the volume.

(4aii)

– Conservation of mass and energy

– Conservation of linear momentum, conservation of angular momentum

– Conservation of electric charge

(4bi)

– Lax and broken regulation systems

– Highly-priced and valued animal parts, products, and pets

(4bii)

– Elephants

– Rhinos

– Tigers

– Gorillas

– Sea turtles

(4c)

– Loss of biodiversity, migration of wildlife

– Exological imbalance

–  Soil erosion

–  Disruption in hydrological cycle of water catchment area

(4di)

A blood transfusion is a routine medical procedure in which donated blood is provided to you through a narrow tube placed within a vein in your arm. This potentially life-saving procedure can help replace blood lost due.

(4dii)

An antigen is any substance to which the immune system can respond. For example, components of the bacterial cell wall can trigger severe and immediate attacks by neutrophils.

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(3ai)

Ecological niche refers to the specific portion of a habitat which is occupied by a particular species or organism

(3aii)

– Food

– Shade

– Wind breaker

– Absorb Carbobdioxide

– Promote Photosynthesis for oxygen provision

(3bi)

[Pick any two]

– Overview of the content of the environment

– To have different outcome

– To know the range of organisms in that area

(3bii)

– Simple random sampling

– Systematic Sampling

– Convenience Sampling

– Clustered Sampling

(3c)

– Whorl

– Compound

– Loop

– Arch

(3di)

Garden peg ( Potassium Satiuim)

(3dii)

[Pick any two]

– Flower are bisexual

-They are self pollinating

– Short lifespan

– Some seed are round others are wrinkled.

CONCLUSION:- Oliveloaded will never ask for any more than the date and subjects and mind you this answers is consist two answers which is chemistry and biology answers reason why we uploaded it here to signify the correct answers from social media thanks so much.

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