Chemistry Past Questions And Answers
The sulphide which is insoluble in dilute hydrochloric acid is
- A. FeS
- B. CuS
- C. ZnS
- D. Na2S
The volume occupied by 1.58g of a gas at S.T.P is 500cm^3. What is the relative molecular mass of the gas? [ G.M.V at S.T.P = 22.4dm^3 ]
- A. 28
- B. 32
- C. 44
- D. 71
A side effect of soft water is that
- A) it gives offensive taste
- B) excess calcium is precipitated
- C) it attacks lead contained in pipes
- D) it encourage the growth of bacteria
Which of the following is not true about benzoic acid?
- A) It is aromatic in nature
- B) It can be manufactured from methylbenzene
- C) It has molecular formula C6 H6COOH
- D) It sublimes readily
When alkanols react with sodium, the gas evolved is
- A. hydrogen
- B. oxygen
- C. methane
- D. ethyne
If 0.2g of a salt is required to saturate 200cm3 of water at room temperature, what is the solubility of the salt?
- A. 0.2gdm-3
- B. 1.0gdm-3
- C. 2.0gdm-3
- D. 5.0gdm-3
If the oxidation potential of Mg and Al are +2.37 volts and + 1.66 volts respectively, then the Mg would?
- A. not replace Al
- B. be replaced by Al
- C. remain in the solution
- D. replace Al
Species that occur in a reaction pathway but not in the overall reaction are known as
- A. Reactants
- B. Inhibitors
- C. Products
- D. Intermediates
(a) Balance the nuclear equation below and hence identify Y.
\(^{238}_{94}U \to ^{234}_{92}Th + Y\)
(b) In a tabular form, state two of the observations in the cathode ray experiment and the corresponding deductions.
View Discussion (0)WAEC 1990 THEORYAn element having the atomic number 17 will resemble which of the following elements having atomic number as given below?
- A. 33
- B. 35
- C. 18
- D. 19