Em tham khảo nha:
\(\begin{array}{l}
a)\\
{n_{CaC{O_3}}} = \dfrac{m}{M} = \dfrac{{250}}{{100}} = 2,5\,mol\\
{n_{Ca}} = {n_{CaC{O_3}}} = 2,5\,mol\\
{m_{Ca}} = n \times M = 2,5 \times 40 = 100g\\
{n_C} = {n_{CaC{O_3}}} = 2,5\,mol\\
{m_C} = n \times M = 2,5 \times 12 = 30g\\
{n_O} = 3{n_{CaC{O_3}}} = 7,5\,mol\\
{m_O} = n \times M = 7,5 \times 16 = 120g\\
b)\\
{N_{CaC{O_3}}} = n \times 6 \times {10^{23}} = 2,5 \times 6 \times {10^{23}} = 1,5 \times {10^{24}} \text{ phân tử}\\
{N_{Ca}} = n \times 6 \times {10^{23}} = 2,5 \times 6 \times {10^{23}} = 1,5 \times {10^{24}} \text{ nguyên tử}\\
{N_C} = n \times 6 \times {10^{23}} = 2,5 \times 6 \times {10^{23}} = 1,5 \times {10^{24}} \text{ nguyên tử}\\
{N_{{O_{}}}} = n \times 6 \times {10^{23}} = 7,5 \times 6 \times {10^{23}} = 4,5 \times {10^{24}} \text{ nguyên tử}
\end{array}\)
