Neco Chemistry Past Questions and Answers

Question 86:

• NECO 2008

Which of these arrangement of elements is in order of increasing ionization energy?

A. Boron, Carbon, Flourine, Nitrogen
B. Boron, Carbon, Nitrogen, Flourine
C. Carbon, Boron, Nitrogen, Flourine
D. Flourine, Nitro9en, Carbon, Boron
E. Nitrogen, Flourine, Carbon, Boron

Question 87:

• NECO 2008

The gas in air used by plants for photosynthesis is ____________

A. Argon
B. Carbon (IV) oxide
C. Nitrogen
D. Oxygen
E. Water vapour.

Question 88:

• NECO 2008

When sodium hydroxide solution is added to a solution of zinc salt, the white precipitate formed re-dissolve in excess sodium hydroxide because ____________

A. Sodium hydroxide is a strong alkali
B. Sodium is more reactive than zinc
C. Zinc is more reactive than sodium
D. Zinc hydroxide is amphoteric
E. Zinc hydroxide is unstable

Question 89:

• NECO 2008

A chemical system is at equilibrium when ____________

A. δ G is positive
B. δ G is zero
C. δ S is negative
D. δ S is positive
E. δ S is zero.

Question 90:

• NECO 2008

Brownian motion explains ____________

A. Boyle’s law
B. Collision theory
C. Laws of chemical combination
D. Molecular motion in liquids and gases
E. Vibrational motion in liquids.