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Chemistry Past Questions and Answers

Jamb 1997 Chemistry Questions

Question 41:
25 cm3 of 0.02 M KOH neutralized 0.03 g of a monobasic organic acid having the general formula CnH2n + 1 COOH. The molecular formula of the acid is?
(C = 12, H = 1, O = 16)
  • A HCOOH
  • B C<sub style='font-size: smaller;'>2</sub>H<sub style='font-size: smaller;'>5</sub>COOH
  • C CH<sub style='font-size: smaller;'>3</sub>COOH
  • D C<sub style='font-size: smaller;'>3</sub>H<sub style='font-size: smaller;'>7</sub>COOH
View Answer & Explanation
Question 42:
(1 /(2) N2(g) + (1) / (2)O2(g) → NO(g) ∆H° 89 KJ mol-. If the entropy change for the reaction above at 25°C is 11.8 J mol-, calculate the change in free energy. ∆G°, for the reaction at 25°C?
  • A 88.71 KJ
  • B 85.48 KJ
  • C -204.00 KJ
  • D -3427.40 KJ
View Answer & Explanation
Question 43:
Use the graph above to answer this question. A sample, X, solid at room temperature, was melted, heated to a temperature of 358 K and allowed to cool as shown in OPQR. The section PQ indicates that X is
  • A A mixture of salts
  • B A hydrated salt
  • C An ionic salt
  • D A pure compound
View Answer & Explanation
Question 44:
Use the graph above to answer this question. A sample, X, solid at room temperature, was melted, heated to a temperature of 358 K and allowed to cool as shown in OPQR.The section OP suggests that X is in the
  • A Liquid sate
  • B Solid/liquid state
  • C Solid state
  • D Gaseous state
View Answer & Explanation
Question 45:
In the diagram above the gas Y could be
  • A Hydrogen chloride
  • B Oxygen
  • C Carbon (IV) oxide
  • D Chlorine
View Answer & Explanation