The number of Cr atoms in a 26.0 g sample of chromium is x. How many atoms, expressed in terms of x, would be contained in 26.98 g of aluminum (Al)?
A)x
B)x\2
C)2x
D)x+2

Question

Quizplus · Accepted Answer

The number of atoms is proportional to the number of moles. Since the molar mass of Al (26.98 g/mol) is approximately half that of Cr (51.996 g/mol), 26.98 g of Al contains about twice the number of moles, and thus twice the number of atoms, as 26.0 g of Cr.

The Number of Cr Atoms in a 26