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.
Study carefully the reaction represented by the equation below. 2H2O 2(l) → O 2(g) + 2H2O(l). Which of the following will not reaction increase the reaction rate?
AHeating the hydrogen peroxide
BAdding a pinch of MnO2 to the reactant
Cincreasing the concentration of the H2O2
DAdding water to the reactant
EExposing the reactant to sunlight
View Explanation & Discuss
Question 742
waec1992
Methanol is obtained from wood by
Aesterification
Bbacterial decomposition
Ccombustion
Dfractional distillation
Edestructive distillation
View Explanation & Discuss
Question 743
waec1992
The maximum number of electrons that can accommodated in the shell having the principal quantum number 3 is
A3
B9
C10
D18
E32
View Explanation & Discuss
Question 744
waec1992
When steam is passed over white-hot coke, the products are
Acarbon (IV) oxide and nitrogen
Bcarbon (II) oxide and hydrogen
Ccarbon (ll) oxide and nitrogen
Dcarbon (lV) oxide and steam
View Explanation & Discuss
Question 745
waec1991
Which of the following is suitable for determining different isotopes present in an element which exhibits isotopy?
ASensitive weighing balance
BCathoda ray tube
CMass spectrometer
DGeiger muller counter
EEudiometer
View Explanation & Discuss
Question 746
waec1991
Hydrogen is used for the following except
Amanufacturing of ammonia
Bsynthesis of hydrochloric acid
Cextinguishing fire
Dconversion of coal to petrol
Emanufacture of margarine
View Explanation & Discuss
Question 747
waec1991
In solution, aminoethanoic acid (glycine) can be represented as NH+3 CH2COO. This implies that it
Ais soluble in all inorganic liquids
Bcan function as a weak acid or a weak base
Cdoes not form salt with mineral acids
Dis highly acidic
Ecannot form esters with alkanols
View Explanation & Discuss
Question 748
waec1991
river contaminated by alkali waste will have a pH of about.
A1
B3
C5
D7
E9
View Explanation & Discuss
Question 749
waec1991
An organic compound which reacts readily with bromine to form a compound with the formula CH3CHBrCH2Br is
Aethene
Bpropane
Cbutane
Dpropene
Epropyne
View Explanation & Discuss
Question 750
waec1991
When a crystal was added to its solution, it did not dissolve and the solution remained unchanged, showing that the solution was
Aconcentrated
Bsupersaturated
Cunsaturated
Dcolloidal
Esaturated
View Explanation & Discuss
Question 751
waec1991
A current of 4.0 amperes was passed through copper (ll) tetraoxosulphate (IV) solution for one hour using copper electrodes. What was the mass of copper deposited? (Cu = 64, 1F = 96500 C)
A3.2g
B4.8g
C6.4g
D48g
E96g
View Explanation & Discuss
Question 752
waec1991
In which of the following crystals are the particles held by van der Waal's forces only?
ASodium chloride
BIce
CDiamond
DIodine
EQuartz
View Explanation & Discuss
Question 753
waec1991
Compounds that have the same molecular formula but different structures are said to be
Aallotropic
Bpolymorphic
Cpolymeric
Disomeric
Eisotopic
View Explanation & Discuss
Question 754
waec1991
Which of the following properties is not characteristic of electrovalent compounds?
Aformation of crystalline solids
Bsolubility in polar solvents
Chigh vapour pressures
Dhigh melting and boiling points
Eability to conduct electricity in aqueous solution
View Explanation & Discuss
Question 755
waec1991
How many principal electronic shells has an atom whose electronic configuration is shown below? 1s22s22p63s1
A1
B2
C3
D4
E11
View Explanation & Discuss
Question 756
waec1991
Which of the following is not a direct petroleum product?
AMethane
BEthanol
CPetrol
DVaseline
EKerosene
View Explanation & Discuss
Question 757
waec1991
Which of the reactions represented by the following equations will take place at room temperature?
AC 6 H2O → CO + H2
BCuO + H2 → Cu + H2O
CN2 + 3H2 → 2NH3
D2Na + 2H2O → 2NaOH + H2
E2Fe + 3CI2 → 2FeCI3
View Explanation & Discuss
Question 758
waec1991
When starch undergoes complete enzyme-catalyzed hydrolysis, the resulting product is
Aglucose
Bmaltose
Csucrose
Dfructose
Ecellulose
View Explanation & Discuss
Question 759
waec1991
In the redox reaction represented by the following equation: Cu2+aq + Zn(s) → Cu(s) + Zn2+
Athe oxidation number of copper increases
Bcopper (ll) ions are reduced to copper atoms
Czinc atoms are reduced to zinc ions
Dcopper (ll) ions donate electrons to zinc atoms
View Explanation & Discuss
Question 760
waec1991
The ratio of reactants to products is 1: 3: 2 in the reaction represented by the equation below: N2,/SUB> (g) → 2NH3(g) which of the following law is demonstrated by this?
