Question

which si unit is used to measure the number of atoms in different elements? grams moles seconds candelas

Explanation:

To determine the SI unit for measuring the number of atoms in different elements, we analyze each option:

• Grams measure mass, not the number of atoms.
• Moles are the SI unit for the amount of substance, representing a specific number of particles (atoms, molecules, etc.).
• Seconds measure time.
• Candelas measure luminous intensity.

So, moles are used to measure the number of atoms in elements.

Answer:

B. moles