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Saturday, 03 October 2026
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Chemistry Past Questions and Answers

Topic: Solubility

Jamb Chemistry Questions - Solubility

Question 1:
How many grams of HBr would exactly be required to react with 2 g of propyne? (C =12, H=1, Br = 80)
  • A 4. 1 g
  • B 6. 1 g
  • C 8. 1g
  • D 16.2g
View Answer & Explanation
Question 2:
Which of the following derivatives of nitrogen affords an aqueous solution having a pH of less that 7?
  • A N<sub style='font-size: smaller;'>2</sub>O
  • B NO
  • C NO<sub style='font-size: smaller;'>2</sub>
  • D NaNO<sub style='font-size: smaller;'>3</sub>
  • E NH<sub style='font-size: smaller;'>3</sub>
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Question 3:
Magnesium ribbon was added to each of the following aqueous solution in turn: H2SO4, AgNO3, HNO3, HCl, NH3, HCl, NH3. In which case does the magnesium become covered with a dark precipitate?
  • A H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub>
  • B AgNO<sub style='font-size: smaller;'>3</sub>
  • C HNO<sub style='font-size: smaller;'>3</sub>
  • D NH<sub style='font-size: smaller;'>3</sub>
  • E HCl
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Question 4:
In the preparation of some pure crystals of Cu (NO3)2 starting with CuO, a student gave the following statements as steps he employed. Which of these shows a flaw in his report ?
  • A Some CuO was reacted with excess dilute H<sub style='font-size: smaller;'>2</sub>SO<sub style='font-size: smaller;'>4</sub>
  • B The solution was concentrated
  • C When the concentrate was cooled, crystals formed were removed by filtration
  • D The crystals were washed with very little cold water
  • E The crystals were then allowed to dry
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Question 5:
The solubility curves of four substances are shown in the figure above. Which of the four substances would crystallize from a saturated solution cooled from 353K(80oC)to 323K(50[sup][/sup]C)?
  • A P and Q
  • B P and R
  • C P and S
  • D R and S
  • E Q and R
View Answer & Explanation