Question

use the mole quick check
for an element, how does avogadros number connect the atomic and macroscopic scales? (1 point)
it describes the number of grams in 1 mole of an element.
it describes the number of atoms in 1 mole of an element.
it describes the number of atoms in 1 gram of an element.
it describes the number of moles in 1 gram of an element.

Explanation:

Avogadro's number (\(N_A = 6.022\times10^{23}\text{ mol}^{-1}\)) is defined as the number of entities (such as atoms, molecules, ions) in one mole of a substance. On the atomic scale, it represents the number of atoms. On the macroscopic scale, one mole is a measurable amount. So, it connects the two scales by giving the number of atoms in 1 mole of an element.

• The number of grams in 1 mole of an element is given by the molar mass (\(M\)), not Avogadro's number.
• The number of atoms in 1 gram of an element is calculated as \(\frac{N_A}{M}\) (using \(n=\frac{m}{M}\) and \(N = nN_A\)), not directly by Avogadro's number.
• The number of moles in 1 gram of an element is \(\frac{1}{M}\) (from \(n=\frac{m}{M}\)), not related to Avogadro's number in that context.

Answer:

It describes the number of atoms in 1 mole of an element.