Periodic Classification of Elements

Which of the following correctly represent decreasing order of chemical reactivity of elements:

• Na > Mg > Al > Si

• Mg > Na > Al > Si

• Si > Al > Mg > Na

• Al > Si > Na > Mg

Which of the following elements has highest valency:

• Na

• Si

• Ar

• P

By considering their position in the periodic table, which one of the following elements would you expect to the have maximum non-metallic character:

• B

• Be

• N

• F

Which of the following elements will lose one electron to achieve the nearest inert gas electron configuration?

• F

• O

• K

• C

Assertion(A): Respiration is an endothermic reaction. Reason(R): Respiration is a process in which glucose combines with oxygen to produce carbon-dioxide and water along with the release of some energy.

• Both A and R are true and R is the correct explanation of A.

• Both A and R are true and R is not the correct explanation of A.

• A is true but R is false.

• A is false but R is true.

Which element is the most reactive?

• X

• Y

• Z

Which element is the least reactive?

• X

• Y

• Z

Name the oxidizing agent in the following reaction:

• MnO₂

• 4HCl

• Mn

• O₂

• HCl

Name the reducing agent in the following reaction:

• MnO₂

• 4HCl

• Mn

• O₂

• HCl

Which of the following does not belong to the same homologous series?

• C₂H₄

• C₃H₆

• C₄H₈

• C₅H₁₂