11. Which of the following is an example of a good electrical conductor?

• A) Glass
• B) Wood
• C) Copper
• D) Plastic
• Answer: C

12. Which type of substance allows electric current to pass through it easily?

• A) Insulators
• B) Conductors
• C) Semiconductors
• D) Dielectrics
• Answer: B

13. The conductivity of metals is mainly due to the movement of:

• A) Protons
• B) Neutrons
• C) Electrons
• D) Ions
• Answer: C

14. According to Arrhenius theory, an acid is a substance that:

• A) Increases the concentration of hydroxide ions (OH⁻) in water
• B) Increases the concentration of hydrogen ions (H⁺) in water
• C) Accepts protons
• D) Donates electrons
• Answer: B

15. Arrhenius bases are substances that:

• A) Increase the concentration of hydroxide ions (OH⁻) in water
• B) Increase the concentration of hydrogen ions (H⁺) in water
• C) Donate protons
• D) Accept protons
• Answer: A

16. What is the unit of electrical conductivity?

• A) Ohms
• B) Siemens
• C) Volts
• D) Farads
• Answer: B

17. Which of the following statements best describes Ostwald’s Dilution Law?

• A) It explains the conductivity of electrolytes
• B) It relates the dissociation of weak electrolytes to their dilution
• C) It defines the behavior of strong acids in water
• D) It describes the concentration of ions in a solution
• Answer: B

18. According to Arrhenius theory, the neutralization reaction between an acid and a base produces:

• A) Water only
• B) Salt only
• C) Salt and water
• D) Hydrogen gas
• Answer: C

19. Which of the following substances is an Arrhenius acid?

• A) NaOH
• B) HCl
• C) NH₃
• D) CH₄
• Answer: B

20. A solution of an Arrhenius acid in water will:

• A) Increase the OH⁻ concentration
• B) Decrease the H⁺ concentration
• C) Increase the H⁺ concentration
• D) Have no effect on ion concentrations
• Answer: C