Question

Câți atomi se află în 390g de potasiu?

Answer 1

$N_K=?\\m_K=390g\\\\n_K=\frac {m_K}{A_K}=\frac {390g}{39\frac{g}{mol}}=10 mol \\N_K={N_A}\times {n_K}=6,022\times10^{23} \frac{atomi}{mol}} \times10mol=6,022\times10^{24} atomi \:de \: K$