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Thursday, 18 June 2026
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Chemistry Past Questions and Answers

Topic: Separation of mixtures and purification of chemical substances

Jamb Chemistry Questions - Separation of mixtures and purification of chemical substances

Question 251:
Which of the following has an isomer?
  • A C<sub style='font-size: smaller;'>6</sub>H<sub style='font-size: smaller;'>6</sub>
  • B C<sub style='font-size: smaller;'>2</sub>H<sub style='font-size: smaller;'>6</sub>
  • C C<sub style='font-size: smaller;'>4</sub>H<sub style='font-size: smaller;'>10</sub>
  • D C<sub style='font-size: smaller;'>2</sub>H<sub style='font-size: smaller;'>4</sub>
View Answer & Explanation
Question 252:
An emulsion may be produced by shaking a detergent solution with
  • A Palm wine
  • B Ethanoic acid
  • C Palm oil
  • D Water
View Answer & Explanation
Question 253:
When 50cm2 of a saturated solution of sugar of molar mass 342 g at 40oC was evaporated to dryness, 34.2g of dry solid was obtained. The solubility of sugar at 40oC is
  • A 2.0 mol dm<sup style='font-size: smaller;'>-3</sup>
  • B 3.5 mol dm<sup style='font-size: smaller;'>-3</sup>
  • C 7.0 mol dm<sup style='font-size: smaller;'>-3</sup>
  • D 10.0 mol dm<sup style='font-size: smaller;'>-3</sup>
View Answer & Explanation
Question 254:
Water has the ability to dissolve almost all substance because its molecules has a structure with
  • A One positive end and one neutral end
  • B One positive end and one negative end
  • C Two negative ends
  • D Two positive ends
View Answer & Explanation
Question 255:
When a crystal was added to the clear solution of its salt, the crystal did not dissolve and the solution remained unchange. This showed that the solution was
  • A Supersaturated
  • B Concentrated
  • C Unsaturated
  • D Saturated
View Answer & Explanation