Che0100:Chemistry. Question Paper
Che0100:Chemistry.
Course:Diploma In Agriculture
Institution: Meru University Of Science And Technology question papers
Exam Year:2011
QUESTION ONE – (30 MARKS)
(a) You are given that the subsidiary (azimuthal) quantum number ?? for an electron is 2. Determine: (i) The principal quantum number ?? (2 Mark) (ii) The magnetic quantum number ?? (2 Marks) (b) Write the electronic configuration for the elements whose atomic number are: (i) 15 (2 Marks) (ii) 7 (2 Marks) (iii)21 (2 Marks) (c) Using dots and crosses, show the Lewis structures/symbols for (i) Carbon dioxide [ C = 6, O = 8] (2 Marks) (ii) Fluorine molecule [F = 9] (2 Marks) (d) Define the term, ???? of a solution (2 Marks) (e) Using the molecules ??2??6 and ??2??4 examples, explain the difference between an alkene and an alkane. (6 Marks) (f) Define the following terms as applied to solutions; (i) Solute (2 Marks) (ii) Solvent (2 Marks) (g) An element X may be represented symbolically as ?? ?? ?? (i) What do the letters A and Z represent? (2 Marks) (ii) ???? ?? = 8,?????? ?? = 18, how many neutrons does X have? (2 Marks)
2
QUESTION TWO – (15 MARKS)
(a) How do Bronsted and Lowry define: (i) An acid and, (2 Marks) (ii) A base? (2 Marks) (b) Use an appropriate chemical equation to show how ammonia ????3 reacts with water. In your equation, indicate the conjugate acid/base pairs. (5 Marks) (c) Given that ???? = ??3??+ ????- = 1.0 × 10-14, Calculate the pH of 2.5 × 10-4?? ???????? (6 Marks)
QUESTION THREE – (15 MARKS)
(a) State the law of multiple proportions (2 Marks) (b) Sulphur dioxide reacts with oxygen as shown 2????2(??) + ??2(??) ? 2????3(??) and an equilibrium is established. (i) Write the expression for the equilibrium constant ???? for this reaction. (2 Marks) (ii) What will be the effect of removing oxygen from the system? (2 Marks) (iii)What will be the effect of removing sulphur trioxide from the reaction mixture on the position of the equilibrium and on the quantities of the gases mixture? (4 Marks) (c) 17.8?? ???? ????2????4 was dissolved in water to make a 500????3 solution. Calculate the molarity of the resulting solution. (???? = 23, ?? = 16, ?? = 32) (5 Marks)
QUESTION FOUR – (15 MARKS)
(a) Identify the quantum numbers which describe an electron’s property. (4 Marks) (b) Draw the orbital diagram for the element whose atomic number is 15. (2 Marks) (c) Calculate the wavelength in nanometer of the Third Line in the Bracket series for the hydrogen atom ??1 = 4,???? = 10967 758??-1 (5 Marks) (d) The element lithium whose atomic number is 3 belongs to group IA in the periodic chart of the elements. Lithium however, shows pronounced similarities in properties which resemble those of Magnesium in group IIA. In what ways does lithium show diagonal relationship with Magnesium? (4 Marks)
QUESTION FIVE – (15 MARKS)
(a) Write the structural formulae of the compounds named below
3
(i) Ethyne (ii) Prop-2-ene (iii)Methanamine (6 Marks)
(b) Give the systematic (IUPAC) names of the following compounds: (8 Marks) (i) CH3CH2CH2F
(ii) CH3CH = CHCH3
O || (iii)CH3CH2C-OH
(iv)
(c) Using an orbital diagram, show the ????3 hybridization in the carbon atom (C=6) (1 Mark)
More Question Papers