Study and practice Chemistry past questions with answers and detailed explanations. Then test your knowledge using our interactive CBT practice platform and prepare confidently for your upcoming examinations.
What type of reaction occurs between vegetable oil and plant ash extract?
ADisplacement
BDehydration
CNeutralization
DSaponiflication
View Explanation & Discuss
Question 1092
waec2006
Which of the following industrial processes is chlorines not used?
AProduction of polyvinylchloride (PVC)
BManufacturing of hydrochloric acid
CManufacturing of common salt
DManufacturing of domestic bleach
View Explanation & Discuss
Question 1093
waec2006
In the reaction represented by the equation. 5Fe 2+(aq) + MnO-4(aq) + 8H+(aq) → 5Fe3+(aq) + Mn2+(aq) + 4H2O(l) which species is reduced?
AFe2+
BMnO-4
CH+
DFe3+
View Explanation & Discuss
Question 1094
waec2006
Consider the reaction: 2AI(s) + 6H+(aq) → 2AI3+(aq) + 3H2(g). What is the total number of moles of electrons transferred from the aluminium atoms to the hydrogen ions?
A3
B4
C5
D6
View Explanation & Discuss
Question 1095
waec2006
Metals can be extracted from their ores by a process involving
Areduction
Boxidation
Chydrolysis
Ddecomposition
View Explanation & Discuss
Question 1096
waec2006
The oxidation number of iodine in the iodate ion (IO -3) is
A-5
B-1
C+1
D+5
View Explanation & Discuss
Question 1097
waec2006
Electrolysis is applied in the following processes except
Aelectroplating
Bextraction of aluminium
Cextraction of iron
Dpurification of copper
View Explanation & Discuss
Question 1098
waec2006
Consider the reaction represented by the equation: 2SO\(_{2(g)}\) + O\(_{2(g)}\) ⇌ 2SO\(_{3(g)}\); ∆H = - 197 kJmol\(^{-1}\). Which of the following conditions will not increase the yield of sulphur (VI) oxide?
AIncrease in temperature
BDecrease in temperature
CIncrease in pressure
DAddition of O2 into the mixture
View Explanation & Discuss
Question 1099
waec2006
Which of the following compounds absorbs moisture from the atmosphere and dissolves in it?
AFeCI3
BMgSO4.7H2O
CNa2SO 4
DKCI
View Explanation & Discuss
Question 1100
waec2006
When aqueous ammonia is added to one of the following solutions,a white precipitate which dissolved in excess ammonia is formed Identify the solution.
AZnCl2(aq)
BPb(NO3)2(aq)
CCuSO4(aq)
DFeSO4(aq)
View Explanation & Discuss
Question 1101
waec2006
The indicator used in neutralizing CH3COOH and NaOH solution has pH range of
A3-5
B7-8
C8-103
D10-12
View Explanation & Discuss
Question 1102
waec2006
Which of the following aqueous methods cannot be used to distinguish between a strong acid and a a weak acid?
AConductivity measurement
BMeasurement of pH
CMeasurement of heat of neutralization
DAction on starch iodide paper
View Explanation & Discuss
Question 1103
waec2006
Which of the following processes is an endothermic reaction?
ADissolving NH4CI crystals in water
BAddition of concentrated H2SO4
CDissolving NaOH pellets in water
DPassing SO3 gas into water
View Explanation & Discuss
Question 1104
waec2006
Considered the reaction: H+(aq) + OH -(aq) → H2O (l). The energy change taking place in the reaction above is enthalpy of
Aformation
Bhydration
Cneutralization
Dsolution
View Explanation & Discuss
Question 1105
waec2006
Consider the reaction represented by the equation. 2NaHCO3(s) \(\rightarrow\) 2Na2CO 3(S) + CO 2(g) + H2O(g) what volume of carbon (IV)oxide at s.t.p is evolved when 0. 5 moles of NaHCO3 is heated? [Molar volume = 22.4 dm3 at s.t. p]
A1.12dm3
B2.24dm3
C5.6dm3
D56.0dm3
View Explanation & Discuss
Question 1106
waec2006
If 20 cm3 of distilled water is added to 80cm 3 of 0. 50 mol dm-3 hydrochloric acid, the new concentration of the acid will be
A0.10mol dm-3
B0.20mol dm-3
C0.40mol dm-3
D2.00mol dm-3
View Explanation & Discuss
Question 1107
waec2006
If 1 mole of sodium contains 6 x 1023 atoms, how many atoms are contained in 0.6 g of sodium? [Na = 23]
A1.56 x 1023
B1.56 x 1022
C3.6 x 1023
D3.6 x 1022
View Explanation & Discuss
Question 1108
waec2006
An atom 23892X decays by alpha particle emission to give an atom Y. The atomic number and mass number of Y are
A90 and 234 respectively
B91 and 238 respectively
C92 and 236 respectively
D93 and 238 respectively
View Explanation & Discuss
Question 1109
waec2006
An element X has isotopic masses of 6 and 7. if the relative abundance is 1 to 12.5 respectively, what is the relative atomic mass of X?
