NECO OBJECTIVE MOST REPEATED PAST QUESTIONS ON CRK

Here are some frequently repeated NECO objective questions on Chemistry:

*Chemistry*

1. The periodic table is arranged in order of:
A) Atomic mass
B) Atomic number
C) Electron configuration
D) Valency

Answer: B) Atomic number

1. The chemical symbol for gold is:
A) Ag
B) Au
C) Hg
D) Pb

Answer: B) Au

1. The process of converting a solid directly to a gas is called:
A) Melting
B) Boiling
C) Sublimation
D) Condensation

Answer: C) Sublimation

1. The pH of a strong alkaline solution is:
A) 1-2
B) 7
C) 10-12
D) 14

Answer: C) 10-12

1. The oxidation state of oxygen in water (H2O) is:
A) +1
B) -1
C) -2
D) +2

Answer: C) -2

1. The chemical equation for the reaction between sodium and water is:
A) 2Na + H2O → 2NaOH + H2
B) Na + H2O → NaOH + H
C) 2Na + H2O → Na2O + 2H
D) Na + H2O → NaO + H

Answer: A) 2Na + H2O → 2NaOH + H2

1. The process of separating mixtures based on differences in boiling points is called:
A) Distillation
B) Filtration
C) Sedimentation
D) Decantation

Answer: A) Distillation

1. The chemical symbol for carbon dioxide is:
A) CO
B) CO2
C