WAEC 2025 CHEMISTRY ANSWERS (OBJ & ESSAY)

BEST EXPO RUNZ ASSISTANCE WEBSITE. NO.1 BEST DELIVERY OF EXAM RUNZ

100% GUARANTEE OF GETTING ANSWERS MIDNIGHT..IT’S OUR CULTURE, NO DOUBT

===================================

SECTION A: ANSWER ONE(1) QUESTION ONLY

(1a)
Mass of ozone is 4.8g
The molar mass of ozone is 3 × 16.0 = 48.0g/mol.

Number of moles = mass of ozone / molar mass of ozone
= 4.8/48.0
= 0.1 mol

(1b)
(i) HSO₄⁻
(ii) NO⁻

(1c)
(i) CH₃CHCHCH₃: But-2-ene
(ii) CH₃CH₂COOH: Propanoic acid

(1d)
The statement “an atom is electrically neutral” means that an atom has no overall electric charge. This happens because the number of positively charged protons in the nucleus is exactly equal to the number of negatively charged electrons orbiting around the nucleus.

(1e)
(i) ₁₂Mg: 1s² 2s² 2p⁶ 3s²
(ii) ₁₁Na⁺: 1s² 2s² 2p⁶
(iii) ₇N³⁻: 1s² 2s² 2p⁶

(1f)
An acid salt is a salt formed when a polyprotic acid is only partially neutralized, so it still contains replaceable hydrogen ions. It produces an acidic solution because not all hydrogen ions are replaced.

(1g)
a: Mass number
b: Atomic number

(1h)
(i) Sand and water: Filtration
(ii) Sand and iron filings: Magnetic separation
(iii) Water and ethanol: Fractional distillation

(1i)
(i) Mg₂:
Metallic bonding
(ii) NaBr:
Ionic bonding
(iii) PH₃:
Covalent bonding

(1j)
(i)
Ag < Pb < Zn < Mg < Na
(ii) Sodium (Na)

===================================

SECTION B: ANSWER THREE(3) QUESTION ONLY

(2)

 

 


(3)

 


(4)

 

 


(5)

===================================

COMPLETED….We Remain Your Favourite Site.
Ensure You Subscribe For Your Next Paper 

===================================

Be the first to comment

Leave a Reply

Your email address will not be published.


*