2021
(a)i. With the aid of an equation, explain briefly why aluminum metal is not affected by air.(ii) In the extraction of aluminum from bauxite, state the: - substance used for purifying the ore; - composition of the mixtur…
See more
2021 WAEC SSCE Chemistry Past Questions
Ulearngo is an independent study app. It is not affiliated with, endorsed by, or representing West African Examinations Council (WAEC). Always confirm official exam, admission, registration, syllabus, timetable, and result information from WAEC official website, WAEC Nigeria.
2021
(a) What is the structure of:(i) graphite: (ii) diamond (ii) Explain briefly why diamond is hard and a non-conductor of electricity while graphite is soft and an electrical conductor,(b)i. State what is achieved at each…
See more
2021
(a) In an experiment, 25.0 cm\(^{3}\) of H\(_{2}\)SO\(_{4}\) completely neutralized 24.0 cm\(^{3}\) of a 0.1 50 mol dm\(^{-3}\) aqueous KOH using a suitable indicator.(i) Write a balanced chemical equation for the reacti…
See more
2021
(a)i. State two characteristics of a homologous series.(ii) Explain briefly why there are differences in the reaction of ethane and ethene.(b) When crystals of sodium chloride were warmed with concentrated tetraoxosulpha…
See more
2021
(a) Distinguish between molecular formula and structural formula(b) List three factors that determine the ionization energy of an atom.(c) State the two conditions necessary for the establishment of a chemical equilibriu…
See more
2021
Which of the following scientists discovered the electrons?
See more
2021
A coordinate covalent bond could be formed between?
See more
2021
Electrovalent compounds normally ------------
See more
2021
Which of the following statements about elements in Group VII is correct?
See more
2021
Which of the following pairs of molecules form hydrogen bonds?
See more
2021
The isotopes of neon are represented by the symbols \(^{20}\)\(_{x}\) Ne, \(^{21}\)\(_{y}\) Ne, and \(^{22}\)\(_{z}\) Ne. The relationship between x, y, and z is?
See more
2021
How many molecules of oxygen would occupy a volume of 2.24 cm\(^{3}\) at s.t.p?[Molar volume at s.t.p = 22,400 cm\(^{3}\), Avogadro's number = 6.02 x 10\(^{23}\)]
See more
2021
Consider the following energy profile diagram and use it to answer the question that followsThe energy profile diagram illustrates-------------
See more
2021
Consider the following energy profile diagram and use it to answer the question that followsThe enthalpy change of the reaction is------------
See more
2021
Consider the following energy profile diagram and use it to answer the question that followsThe activation energy of the reaction is
See more
2021
Protons and electrons are called fundamental particles because they----------
See more
2021
The region around the nucleus where electrons can be located is called?
See more
2021
The following ions have the same electron configuration except\(_{8}\)O,\(_{12}\)Mg,\(_{13}\)AI,\(_{17}\)CI
See more
2021
An element, Q, contains 69% of\(^{63}\)Q and 31% of \(^{65}\)Q. What is the relative atomic mass of Q?
See more
2021
Potassium trioxonitrate(V) can be obtained from its solution by----------
See more