Chemistry NECO exam past questions and answers

Chemistry NECO exam past questions and answers

Here they are;

What is the atomic number of carbon?

a) 6

b) 12

c) 14

d) 8

Answer: a) 6

Which of the following is a noble gas?

a) Oxygen

b) Helium

c) Nitrogen

d) Fluorine

Answer: b) Helium

What is the formula for water?

a) CO2

b) H2O

c) CH4

d) O2

Answer: b) H2O

Which subatomic particle has a negative charge?

a) Proton

b) Neutron

c) Electron

d) Nucleus

Answer: c) Electron

What is the chemical symbol for gold?

a) Au

b) Ag

c) Fe

d) Cu

Answer: a) Au

In the periodic table, elements in the same column have similar:

a) Atomic masses

b) Atomic numbers

c) Electron configurations

d) All of the above

Answer: c) Electron configurations

What is the pH of a neutral solution?

a) 7

b) 10

c) 5

d) 0

Answer: a) 7

Which gas makes up the majority of Earth's atmosphere?

a) Oxygen

b) Nitrogen

c) Carbon dioxide

d) Hydrogen

Answer: b) Nitrogen

What is the chemical formula for methane?

a) CH3OH

b) CH4

c) C2H6

d) CO2

Answer: b) CH4

What is the law of conservation of mass?

a) Mass is created in chemical reactions

b) Mass is destroyed in chemical reactions

c) Mass is conserved in chemical reactions

d) Mass is irrelevant in chemical reactions

Answer: c) Mass is conserved in chemical reactions

Which element is the most abundant in the Earth's crust?

a) Silicon

b) Oxygen

c) Aluminum

d) Iron

Answer: b) Oxygen

What is the chemical symbol for sodium?

a) So

b) Na

c) Sn

d) Sd

Answer: b) Na

What is the process of a substance changing from a gas to a liquid called?

a) Sublimation

b) Condensation

c) Evaporation

d) Fusion

Answer: b) Condensation

Which gas gives fizzy drinks their bubbles?

a) Oxygen

b) Carbon dioxide

c) Nitrogen

d) Helium

Answer: b) Carbon dioxide

What is the chemical formula for table salt?

a) NaCl

b) KCl

c) HCl

d) CaCl2

Answer: a) NaCl

What is the formula for sulfuric acid?

a) H2SO3

b) HNO3

c) H2SO4

d) HCl

Answer: c) H2SO4

Which isotope is commonly used in carbon dating?

a) Carbon-12

b) Carbon-13

c) Carbon-14

d) Carbon-16

Answer: c) Carbon-14

What is the chemical symbol for iron?

a) Fe

b) Ir

c) In

d) Au

Answer: a) Fe

What is the formula for methane?

a) CH3OH

b) CH4

c) C2H6

d) CO2

Answer: b) CH4

Which gas do plants absorb during photosynthesis?

a) Oxygen

b) Nitrogen

c) Carbon dioxide

d) Hydrogen

Answer: c) Carbon dioxide