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Saturday, 07 March 2026
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Chemistry Past Questions and Answers

Neco Chemistry Questions

Question 106:
The most efficient absorber of ultraviolet radiation in the atmosphere is ____________
  • A CO2
  • B H2
  • C H2O
  • D 02
  • E O3
View Answer & Explanation
Question 107:
When dust particles collide randomly in a beam of Sunlight, the phenomenon observed is known as ____________
  • A Brownian movement.
  • B Dialysis
  • C Diffusion
  • D Osmosis
  • E Tyndall effect
View Answer & Explanation
Question 108:
\( ^{234}_{90}Th → ^{234}_{91}Pa + X \)
In the nuclear reaction above, X is ____________
  • A \( ^0_1e \)
  • B \( ^0_{-1}e \)
  • C \( ^4_2He \)
  • D \( ^1_0n \)
  • E \( ^1_1p\)
View Answer & Explanation
Question 109:
What is the colour of phenolphthalein indicator in a basic medium?
  • A Blue
  • B Colourless
  • C Orange
  • D Pink
  • E Yellow
View Answer & Explanation
Question 110:
Which of the following will Increase the rate of reaction of Chips of a metal M as shown in the equation below?

M(s)+2HC1(aq) → MCI2 (aq) + H2(g)
  • A Adding some distilled water
  • B Decreasing the temperature
  • C Diluting the hydrochloric acid
  • D Grinding the metal into powder
  • E Increasing the pressure
View Answer & Explanation