Chemistry JAMB, WAEC, NECO AND NABTEB Official Past Questions

2563

In which of the following processes are larger molecules broken down into smaller molecules?

  • A. Vulcanization of rubber
  • B. Hydrogenation of palm oil
  • C. Hydrolysis of starch
  • D. Polymerization
  • E. Esterification
View Answer & Discuss WAEC 1995
2564

The gas produced when a mixture of sodium propanoate and soda lime is heated is

  • A. methane
  • B. pentane
  • C. ethane
  • D. butene
  • E. ethyne
View Answer & Discuss WAEC 1995
2565

Fructose and glucose are classified as carbohydrates because they

  • A. are crystalline white solids
  • B. are energy -giving substances
  • C. are naturally occurring organic compounds
  • D. contain carbon oxygen and hydrogen
  • E. conform to the general formula Cx(H2O)y
View Answer & Discuss WAEC 1995
2566

The following can be obtained directly from the destructive distillation of coal except

  • A. ammoniacal liquor
  • B. coke
  • C. producer gas
  • D. coal gas
  • E. coal tar
View Answer & Discuss WAEC 1995
2567

Which of the following is hydrocarbons is unsaturated?

  • A. Ethane
  • B. Benzene
  • C. Propane
  • D. 2 - methylbutane
  • E. 2,2,4-trimethylpentane
View Answer & Discuss WAEC 1995
2568

The following statements about graphite are correct except that it

  • A. is used as a lubricant
  • B. has a network structure
  • C. contains mobile free electrons
  • D. is good conductor
  • E. is an allotrope of carbon
View Answer & Discuss WAEC 1995
2569

H3O+(aq) + OH-(aq) → 2H2O(l). The heat change accompanying the process represented by the equation above is the heat of

  • A. neutralization
  • B. formation
  • C. solution
  • D. dilution
  • E. hydration
View Answer & Discuss WAEC 1995
2570

Which of the following is not correct of the reaction represented by the equation below? 2C(s) + O2(g) → 2CO(g); ∆H = – xKJ

  • A. there is an increase in entropy ;
  • B. There is anincrease in gaseous volume
  • C. Carbon (lV) oxide is produced
  • D. The oxidation number of carbon increases from 0 to +2
  • E. The reaction is exothermic
View Answer & Discuss WAEC 1995
2571

What mass of copper will be deposited by the liberation of Cu2+ when 0.1F of electricity flows through an aqueous solution of a copper (ll) salt? [Cu = 64]

  • A. 64g
  • B. 32g
  • C. 12.8g
  • D. 6.4g
  • E. 3.2g
View Answer & Discuss WAEC 1995
2572

What mass of copper will be deposited by the liberation of Cu2+ when 0.1F of electricity flows through an aqueous solution of a copper (ll) salt? [Cu = 64]

  • A. 64g
  • B. 32g
  • C. 12.8g
  • D. 6.4g
  • E. 3.2g
View Answer & Discuss WAEC 1995
2573

Sodium chloride cannot conduct electricity in the solid state because it

  • A. is a normal salt
  • B. is highly soluble in water
  • C. is an electrovalent compound
  • D. does not have any effect on litmus
  • E. does not contain mobile ions
View Answer & Discuss WAEC 1995
2574

Alums are classified as

  • A. simple salt
  • B. acid salts
  • C. anhydrous salts
  • D. double salts
  • E. basic salts
View Answer & Discuss WAEC 1995
2575

Consider the reaction represented by the equation below: XO + YO → X + YO2 In the reaction, YO acts as

  • A. an acidic oxide
  • B. a basic oxide
  • C. a reducing agent
  • D. a weak base
  • E. an oxidizing agent
View Answer & Discuss WAEC 1995
2576

A positive brown ring test indicates the presence of

  • A. NO 3
  • B. Fe 3+
  • C. SO 2-3
  • D. CU+
  • E. NO- 2
View Answer & Discuss WAEC 1995
2577

The most suitable method for preparing lead (ll) chloride is by

  • A. action of dilute HCI on PbSO 4
  • B. acts of dilute HCI on lead
  • C. action of dilute HCI on PbCO3
  • D. bubbling chlorine into a solution of Pb(NO3)2
  • E. mixing aqueous solutions Pb(NO3)2 and NaCI.
View Answer & Discuss WAEC 1995
2578

Which of the following species is always present in acidified water?

  • A. NH+4
  • B. O 2-
  • C. HCI
  • D. H3O+
  • E. HNO3
View Answer & Discuss WAEC 1995
2579

A weak acid is one which

  • A. is not corrosive
  • B. is slightly ionized in water
  • C. does not produce salts with alkalis
  • D. does not conduct an electric current in aqueous solution
  • E. forms acid salts with bases
View Answer & Discuss WAEC 1995
2580

What is the percentage by mass of copper in copper in copper (l) oxide (CU2O)? [O = 16; CU =64]

  • A. 88.9%
  • B. 80.0%
  • C. 66.7%
  • D. 20.0%
  • E. 11.1%
View Answer & Discuss WAEC 1995
2581

Which of the following cannot be deduced from the electronic configuration of a transition metal?

  • A. Possession of magnetic property
  • B. Ability to form complex ions
  • C. Position in the Periodic Table
  • D. Variable oxidation states
  • E. Physical properties of the metal
View Answer & Discuss WAEC 1995
2582

Which of the following molecules is linear in shape?

  • A. CH4
  • B. H2O
  • C. NH3
  • D. H2S
  • E. CI2
View Answer & Discuss WAEC 1995
2583

If a solid has a low melting point and dissolves readily in benzene, it would probably

  • A. contain strong electrostatic forces of attraction
  • B. conduct electricity in the molten state
  • C. dissolve in water
  • D. have covalent bonding
  • E. absorb moisture on exposure to air
View Answer & Discuss WAEC 1995