Question

which statement correctly explains how the existence of isotopes affects the concept of the mole for a given element? isotopes cause the number of particles in one mole to be different for each isotopic form of the element, meaning one mole of carbon - 12 has fewer atoms than one mole of carbon - 14 the molar mass (the mass in grams of one mole) for an element is a weighted average because it accounts for the mass and natural abundance of all the elements isotopes the mole concept is rendered unnecessary by isotopes, as scientists must use the individual mass of a specific isotope (like uranium - 235) instead of a standard molar mass isotopes have no effect on the molar mass; the molar mass is fixed by the atomic numbe

Explanation:

One mole always contains Avogadro's number ($6.022\times 10^{23}$) of particles regardless of isotope. The molar mass of an element is calculated as a weighted - average of the masses of its isotopes based on their natural abundances. The mole concept is still relevant even with isotopes. The atomic number determines the element identity but not the molar mass when isotopes are considered.

Answer:

The molar mass (the mass in grams of one mole) for an element is a weighted average because it accounts for the mass and natural abundance of all the element's isotopes