Past Questions And Answers
In the redox reaction represented by the following equation: Cu2++aq Zn(s) → Cu(s) + Zn2+
- A. the oxidation number of copper increases
- B. copper (ll) ions are reduced to copper atoms
- C. zinc atoms are reduced to zinc ions
- D. copper (ll) ions donate electrons to zinc atoms
(a)(i) List three properties of elements which increase generally across a period in the Periodic Table,
(ii) Give two differences between a chemical reaction and a nuclear reaction.
(b) Use the information provided in the table below to answer Questions (i) - (vii).
Atom of Element | P | Q | R | S | T |
Mass Number | 16 | 40 | 35 | 18 | 20 |
Atomic Number | 8 | 20 | 17 | 8 | 10 |
Which of the atoms in the table above:
(i) are isotopes of the same element?;
(ii) contains 18 neutrons?;
(iii) is chemically unreactive?;
(iv) readily forms an ion with two positive charges?
(v) attain an octet structure by accepting one electron?;
(vi) forms ionic bond with R?;
(vii) belongs to the s-block in the Periodic Table?
(c) Describe in outline how each of the following conversions can be carried out in the laboratory. Write appropriate equations for the reactions involved in each case
(i) CuCO\(_3\) to Cu
(ii) MgO to MgSO\(_4\).
View Discussion (0)WAEC 2000 THEORYIn the question below choose the word(s) or phrase(s) whichbest fills the gap(s): Tonye said that he was going to bed because he was .... to do any more work
- A. tired out
- B. very tired
- C. too tired
- D. extremely tired
Price fluctuation is a feature of
- A. common market
- B. imperfect market
- C. supermarkets
- D. market failure
(a) State two advantages of industrialization in Nigeria.
(b) Explain four problems that retard industrialization in Nigeria.
(c) In four ways, describe how the problems in (b) above can be solved.
View Discussion (0)WAEC 2016 THEORYChoose the option nearest in meaning to the word underlined. Because Jamium is soeasily offended, he was not considered for the post of head boy?
- A. irritable
- B. stubborn
- C. troublesome
- D. docile
The logic gates represented in Figure 1 is called
- A. AND gate
- B. NAND gate
- C. NOR gate
- D. OR gate
A major difference between power and authority is that, authority is ________
- A. scarcely exercised
- B. more dependent on coercion
- C. acquired popularly
- D. exercised through force
Petroleum has the following positive contributions to the Nigerian economy except
- A. Generate employment
- B. Source of government revenue
- C. development of mono economy
- D. Infrastructure development
Aromatic and aliphatic hydrocarbons can be distinguished from each other by the?
- A. action of bromine
- B. use of polymerization reaction
- C. action of heat
- D. use of oxidation reaction