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 331: An emulsion paint consists of ? Options:
  A) gas or liquid particles dispersed in liguid
  B) liquid particles dispersed in liquid
  C) solid particles dispersed in liquid
  D) solid particles dispersed in solid
  Show Answer
  The correct answer is B .
• Question 332:

  

  Which of the curves shown in the figure given represents the relationships between the volume(V) and pressure(P) of an ideal gas at constant temperature?

  Options:
  A) 1
  B) 2
  C) 3
  D) 4
  E) 1 and 3
  Show Answer
  The correct answer is C .
• Question 333:

  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 334: The most common ores of iron include Options:
  A) haematite, malachite and limonite
  B) chalcolite, calamine and bornite
  C) magnetite, haematite and bornite
  D) magnetite, chalcolite and bornite
  Show Answer
  The correct answer is C .
• Question 335:

  What is the IUPAC name for the compound CCl${}_4$?

  Options:
  A) Tetrahydrochloride
  B) Tetrachloromethane
  C) Carbon tetrachloride
  D) Chloroform
  Show Answer
  The correct answer is B .
• Question 336: The nitrogen gas obtained by burning an excess of phosphorus in air has a density higher than the nitrogen from nitrogen compounds because the nitrogen from air is contaminated with? Options:
  A) some unburnt phosporus
  B) P₂O₅ vapour
  C) some oxygen
  D) rare gases
  E) carbondioxide
  Show Answer
  The correct answer is D .
• Question 337: One mole of a hydrocarbon contains 48 g of carbon. If it vapour density is 28, the hydrocarbon is? Options:
  A) an alkane
  B) an alkene
  C) an alkyne
  D) aromatic (C = 12, H = 1)
  Show Answer
  The correct answer is B .
• Question 338:

  An element has an atomic number of 8 and a mass number of 16. How many neutrons does this element have?

  Options:
  A) 24
  B) 16
  C) 8
  D) 32
  Show Answer
  The correct answer is C .
• Question 339:

  Na${}_2$CO${}_3$ + 2HCl $\to$ 2NaCl + H${}_2$O + CO${}_2$

  The indicator most suitable for this reaction should have a pH equal to

  Options:
  A) 5
  B) 7
  C) 3
  D) 9
  Show Answer
  The correct answer is C .
• Question 340:

  A cell shorthand notation can be written as A / A${}^{+}$ // B${}^{2+}$ /B. The double slash in the notation represents the 

  Options:
  A) electrolyte
  B) electrodes
  C) salt bridge
  D) solid - liquid interface
  Show Answer
  The correct answer is C .