Chemistry Exam Past Questions and Answers | JAMB, WAEC and NECO

Chemistry is the study of the substances that make up matter. It looks at their properties, how they react with each other, and how these reactions can create new substances.

• Question 961: Fe₂O_3(s) + 2Al_(s) → Al₂O₃ + 2Fe_(s) If the heats of formation of Al₂O₃ and Fe₂O₃ are - 1670 kj mol^-1 and - 822 kj mol^-1 respectively, the enthalpy change in kj for the reaction is ? Options:
  A) +2492
  B) +848
  C) -848
  D) -2492
  Show Answer
  The correct answer is C .
• Question 962:

  

  The functional groups present in the compound above are

  Options:
  A) alkene and halo-group
  B) hydroxyl and chloro-group
  C) alkene and chloro-group
  D) hydroxyl and halo-group
  Show Answer
  The correct answer is B .
• Question 963:

  

  Half-cell reaction. From the data above , it can be deduced that the most powerful reducing agent of the four metals is

  Options:
  A) Cu
  B) Fe
  C) Ba
  D) Zn
  Show Answer
  The correct answer is C .
• Question 964: The group IA metals are not found free in nature because they Options:
  A) are very reactive and unstable
  B) are malleable and ductile
  C) have high melting and boiling point
  D) conduct heat and electricity
  Show Answer
  The correct answer is A .
• Question 965: Which of the following, in clear solution, forms a white precipitate when carbon (IV) oxide is bubbled into it for a short time? Options:
  A) KOH
  B) NaOH
  C) Ca(OH)₂
  D) AI(OH)₃
  Show Answer
  The correct answer is C .
• Question 966:

  The electronic configuration of element Z is 1s${}^2$ 2s${}^2$ 2p${}^6$ 3s${}^2$ 3p${}^1$. What is the formula of the compound formed between Z and tetraoxosulphate (VI) ion.

  Options:
  A) Z${}_3$(SO${}_4$)${}_2$
  B) ZSO${}_4$
  C) Z${}_2$ SO${}_4$
  D) Z${}_2$(SO${}_4$)${}_3$
  Show Answer
  The correct answer is D .
• Question 967:

  Who proposed the planetary model of the atom with electrons orbiting the nucleus?

  Options:
  A) Erwin Schrödinger
  B) Ernest Rutherford
  C) Niels Bohr
  D) J.J. Thomson
  Show Answer
  The correct answer is C .
• Question 968:

  An organic functional group which can likely decolorize ammoniacal silver nitrate is?

  Options:
  A) alkene
  B) alkane
  C) alkyne
  D) alkanol
  Show Answer
  The correct answer is C .
• Question 969:

  

  The I.U.P.A.C name for the compound

  Options:
  A) 2-methyl-3-pentene
  B) 4-methyl-2-pentane
  C) 2-methyl-2-pentene
  D) 4-methylpent-2-ene
  E) 2-methyl-3-pentane
  Show Answer
  The correct answer is D .
• Question 970:

  What is the concentration of a solution containing 2g of NaOH in 100cm³ of solution?

  [Na=23, O=16, H=1]

  Options:
  A) 0.05 moldm^-3
  B) 0.30 moldm^-3
  C) 0.50 moldm^-3
  D) 0.40 moldm^-3
  Show Answer
  The correct answer is C .