Neco Chemistry Past Questions and Answers

Question 106:

• NECO 2008

The most efficient absorber of ultraviolet radiation in the atmosphere is ____________

A. CO₂
B. H₂
C. H₂O
D. 0₂
E. O₃

Question 107:

• NECO 2008

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

Question 108:

• NECO 2008

\( ^{234}_{90}Th → ^{234}_{91}Pa + X \)
In the nuclear reaction above, X is ____________

A. \( ^0_1e \)
B. \( ^0_{-1}e \)
C. \( ^4_2He \)
D. \( ^1_0n \)
E. \( ^1_1p\)

Question 109:

• NECO 2008

What is the colour of phenolphthalein indicator in a basic medium?

A. Blue
B. Colourless
C. Orange
D. Pink
E. Yellow

Question 110:

• NECO 2008

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