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(a) Define each of the following terms and indicate one use of each: (i) Nuclear Fission (ii) Nuclear Fusion (b) Alpha particle emission by 23592 U produces an element A. Beta particle emission by the particle A produces another element B. Element B also undergoes alpha particle emission to produce 22789Ac. Write balanced equation to represent the above statement. (c) The models below represent the filling of orbitals in an atom: State which rule(s) is/are violated or obeyed by each model. (d) Explain why the boiling point of H2S with relative molar mass of 34 is lower than that of H2O with relative molar mass of 18. (e) HCl is passed into each of the following elements: (i) water (ii) methylbenzene I. State the effect of each solution on blue litmus paper. II. Compare the electrical conductivities of the two solution. (f) Zinc dust is added to copper (II) tetraoxosulphate (VI) solution. State (i) what is observed (ii) the type of reaction that occurs (WAEC June 2001(Essay) Q. 1)
(a) What is the anhydride of each of the following acids? (i) H2SO4 (ii) HNO3 (b) Classify each of the following as normal salt/basic salt/double salt (i) sodium hydrogen trioxocarbonate (ii) iron III chloride (iii) sodium ethanoate (WAEC June 1991 (Essay) Q.2)
(a) When MgSO4, XH2O crystals were exposed to atmosphere for several days, there was a loss in mass (i) What name is given to the phenomenon? (ii) Give another example of a compound that exhibits this phenomenon. (b) If 0.50mol of MgSO4, XH2O has a mass of 123g. Calculate the value of X.[H=1; O=16;Mg=24;S=32][WAEC June 1994 Q.6]
(a) (i) What is meant by hydrocarbon? (ii) A hydrocarbon consists of 92.3% carbon. If its vapour density is 39, determine its molecular formula.(H=1;C=12) (b) (i) Outline a suitable laboratory procedure for obtaining ethanol from cassava tubers.(ii) List two laboratory reagents used for oxidizing ethanol to ethanoic acid (c) What name is given to:(i) conversion of alkanols to alkanoates;(ii) breakdown of proteins to amino acids (iii) conversion of oils to fats (iv) alkaline hydrolysis of fats and oils. (WAEC June 1994 (Essay) Q.12)
