Which unit measures the amount of substance at molecular level?

Which unit measures the amount of substance at molecular level?

• A. Meter
• B. Mole
• C. Kelvin
• D. Candela

Answer: (B)

The mole is the unit used to quantify how much of a substance exists in terms of the number of particles. One mole corresponds to Avogadro’s number, about 6.022 x 10^23 particles, linking the microscopic world of atoms and molecules to macroscopic amounts. This base SI unit lets us relate mass to quantity, since the mass of one mole equals the substance’s molar mass in grams. The other options measure different properties: meter for length, Kelvin for temperature, and candela for luminous intensity. So the mole uniquely serves as the unit for amount of substance at the molecular level.

The mole is the unit used to quantify how much of a substance exists in terms of the number of particles. One mole corresponds to Avogadro’s number, about 6.022 x 10^23 particles, linking the microscopic world of atoms and molecules to macroscopic amounts. This base SI unit lets us relate mass to quantity, since the mass of one mole equals the substance’s molar mass in grams. The other options measure different properties: meter for length, Kelvin for temperature, and candela for luminous intensity. So the mole uniquely serves as the unit for amount of substance at the molecular level.