Waec 1988 Chemistry Past Questions And Answers
Water gas is a mature of
- A Co2 and H2
- B. CO and H2O
- C. Co and H2
- Co2 and Co
During the electrolysis of dilute tetraoxosulphate (IV) acid solution 0.05 mole of electrons were passed. What volume of gass was produced at the anode? (Gaseous Molar volume= 22.4dm3 at s.t.p) Half cell electrode potential
- A. 0.224dm3
- B. 0.280dm3
- C. 0.560dm3
- D. 2.24dm3
Which of the following is not a naturally occuring iron ore?
- A. FeCl2
- B. Fe2O3
- C. FeCO3
- D. FeS2
When Copper (II) chloride solution is treated with excess aqueous ammonia, a deep blue solution results. This is due to the presence of
- A. (CuNH4)3+ ion
- B. (CuCl4)2- ion
- C. (Cu(NH3)4)2+ ion
- D. (Cu(OH)4)2- ion
Causes of hardness of water include the presence of?
- A. calcium tetraoxsulphate (VI).
- B. Magnesium tetraoxosulphate (VI)
- C. Calcium hydrogen trioxocarbonate(IV)
- D. Magnesium hydrogen trioxcocarbonate (IV)
Which of the following equations represents the reaction of chlorine with hot concentrated sodium hydroxide solution?
- A. 2KOH + CI2 ---------->KClO + KCI+H2O
- 4KOH + 2Cl2 ----------->4KCl +2H2O + O2
- C. 6KOH + 3Cl2 ---------> KClO3 + 5KCl + 3H2O
- D. 2KOH + CI --------> 2KCI + H2O
Potassium and sodium show similar chemical properties because they?
- A. belong to the same group in the Periodic table
- B. have equal number of electrons in their outermost shells.
- C. both exist in the + 1 oxidation state in their compound
- D. belong to the same period in the Periodic Table
Which of the following correctly explains why iodine crystals change directly into the gaseous state when heated?
- A. Iodine crystals sublime
- B. Iodine crystals molecules are held together by weak forces
- C. Iodine atoms are held together by strong forces
- D. Iodine molecules are covalent
Bubbing of carbon (IV) oxide into calcium hydroxide solution results in the formation of
- A. Ca(HCO3)2
- B. CaCO3
- C. CaO
- H2CO2
Which of the following does not affect the rate of a chemical reaction?
- A. Concentration of the reactants
- B. Addition or presence of catalyst
- C.the enthalpy change of the reaction
- D. Size of the reacting particle