Question

Determine o número de átomos existentes 40 g de átomos de cromo (Cr: MMg = 52 g/mol). ​

Answer 1

$\large\boxed{\begin{array}{l}\sf 52~g\longrightarrow 1~mol\\\sf 40~g\longrightarrow x\\\sf 52x=40\\\sf x=\dfrac{40}{52}\\\\\sf x=0,76~mols\end{array}}$