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.
Which of the following compounds absorbs moisture from the atmosphere and dissolves in it?
AFeCI3
BMgSO4.7H2O
CNa2SO 4
DKCI
View Explanation & Discuss
Question 462
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 463
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 464
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 465
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 466
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 467
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 468
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 469
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 470
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 471
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?
A6.0
B6.1
C6.9
D7.0
View Explanation & Discuss
Question 472
waec2006
How many orbitals are in the d-sub shell?
A1
B3
C5
D7
View Explanation & Discuss
Question 473
waec2005
In which of the following processes is biotechnology not applied?
AManufacture of drugs
BTreatment of domestic sewage
CProduction of alcoholic beverages
DElectroplating of metals
View Explanation & Discuss
Question 474
waec2005
Which of the following substance is an alloy of lead?
ABrass
BDuralumin
CStainless steel
DSoft solder
View Explanation & Discuss
Question 475
waec2005
Which of the following pairs of solutions will produce a precipitate when mixed?
APb(NO3)2(aq) and NaCI(aq)
BMgSO4(aq) and HCI(aq)
CZnCI2(aq) and NaSO4(aq)
DNaOH(aq) and HNO3(aq)
View Explanation & Discuss
Question 476
waec2005
Hardness in water can be removed by adding
Acopper (ll) tetraoxosulphate (IV)
Bsodium trioxocarbonate (IV)
Csodium chloride
Dalum
View Explanation & Discuss
Question 477
waec2005
Ethyne undergoes the following reactions except
Apolymerisation
Baddition
Csubstitution
Desterification
View Explanation & Discuss
Question 478
waec2005
Fats are classified as
Ahydrocarbons
Balkanoates
Calkanols
Dcarbohydrates
View Explanation & Discuss
Question 479
waec2005
The colour of the solution formed when ethyne reacts with an acidic solution of potassium tetraoxomanganate (VII) is
Apurple
Bcolourless
Cgreen
Dpink
View Explanation & Discuss
Question 480
waec2005
Which of the following substances is a non-reducing sugar?
