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 311: The salt formed from strong acid and a strong base is Options:
  A) complex
  B) neutral
  C) basic
  D) acidic
  Show Answer
  The correct answer is B .
• Question 312: CO_g + H₂O_g $\to$ _2g + H_2g $\mathrm{\Delta }$H = -4100J. Which of the following factors favour the formation of hydrogen in the above reaction? i. high pressure. ii. low pressure iii. high temperature iv. use of excess steam Options:
  A) i, iii and iv
  B) iii only
  C) ii, iii and i
  D) iv only
  Show Answer
  The correct answer is D .
• Question 313: Methylethanoate reacts with ammonia to yield? Options:
  A) mettylamine and ethanol
  B) ethylamine and methanol
  C) methanamide and ethanol
  D) ethanamide and methanol
  Show Answer
  The correct answer is D .
• Question 314: The radioactive emission with the least ionization power is Options:
  A) $\alpha -particles$
  B) X-rays
  C) $\gamma -rays$
  D) $\beta -rays$
  Show Answer
  The correct answer is C .
• Question 315: Which of the following is arranged in order of increasing electronegativity? Options:
  A) Chlorine, aluminium, magnesium, phosphorus, sodium
  B) sodium, magnesium, aluminium, phosphorus, chlorine
  C) Chlorine, phosphorus, phosphorous, aluminium, magnesium, sodium
  D) Sodium, chlorine, phosphorus, magnesium, aluminium
  Show Answer
  The correct answer is B .
• Question 316:

  Which of the following are chemical changes?

  I. cooking of food
  II. digestion of food
  III. freezing of water
  IV. water is heated up

  Options:
  A) I and II
  B) I, II, and III
  C) III and IV
  D) all of the above
  Show Answer
  The correct answer is A .
• Question 317:

  Which of the following types of alkanols undergo oxidation to produce alkanoic acids.I. Primary alkanols

  II. Secondary alkanols

  III. Tertiary alkanols

  Options:
  A) I, II and III
  B) I and II only
  C) III only
  D) I only
  Show Answer
  The correct answer is D .
• Question 318: Flow of current in electrolytes is due to the movement of Options:
  A) electrons
  B) Holes and electron
  C) Ions
  D) Charges
  Show Answer
  The correct answer is C .
• Question 319: (1 /(2) N_2(g) + (1) / (2)O_2(g) → NO_(g) ∆H° 89 KJ mol^-. If the entropy change for the reaction above at 25°C is 11.8 J mol^-, calculate the change in free energy. ∆G°, for the reaction at 25°C? Options:
  A) 88.71 KJ
  B) 85.48 KJ
  C) -204.00 KJ
  D) -3427.40 KJ
  Show Answer
  The correct answer is D .
• Question 320:
  

  Use the section of the periodic table above to answer this question.

  Which of the indicate an alkali metal and a noble gas respectively?

  Options:
  A) M and E
  B) G and E
  C) R and L
  D) G and L
  Show Answer
  The correct answer is D .