Search SchoolNGR

Thursday, 11 June 2026
Register . Login

Chemistry Past Questions and Answers

Jamb 2019 Chemistry Questions

Question 81:
Elements X and Y have electronic configurations 1s\(^2\)2s\(^2\)2p\(^4\) and 1s\(^2\)2s\(^2\)2p\(^6\)3s\(^2\)3p\(^1\) respectively. When they combine, the formula of the compound formed is
  • A XY
  • B X\(_2\)Y
  • C Y\(_2\)X\(_3\)
  • D X\(_2\)Y\(_3\)
View Answer & Explanation
Question 82:
By what amount must the temperature of 200cm\(^3\) of Nitrogen at 27°C be increased to double the pressure if the final volume is 150cm\(^3\) (Assume ideality)
  • A 150°C
  • B 177°C
  • C 75°C
  • D 120°C
View Answer & Explanation
Question 83:
The combustion of carbon(ii)oxide in oxygen can be represented by equation.
2CO + O\(_2\) → 2CO\(_2\)
Calculate the volume of the resulting mixture at the end of the reaction if 50cm\(_3\) of carbon(ii)oxide was exploded in 100cm\(_3\) of oxygen
  • A 75cm\(^3\)
  • B 125cm\(^3\)
  • C 100cm\(^3\)
  • D 50cm\(^3\)
View Answer & Explanation
Question 84:
When ammonia and hydrogen ion bond together to form ammonium ion, the bond formed is called
  • A Electrovalent bond
  • B Co-ordinate bond
  • C Ionic bond
  • D Covalent bond
View Answer & Explanation
Question 85:
Which of the following represents the kind of bonding present in ammonium chloride?
  • A Ionic only
  • B Covalent only
  • C Ionic and dative covalent
  • D Dative covalent
View Answer & Explanation