Đáp án:
\(\begin{array}{l}
a)\\
{M_S} = 32dvC\\
b)\\
{M_{Na}} = 23dvC
\end{array}\)
Giải thích các bước giải:
\(\begin{array}{l}
a)\\
{M_S} = {p_S} \times {m_p} + {n_S} \times {m_S} + {e_S} \times {m_e}\\
\,\,\,\,\,\,\,\,\, = 16 \times 1,6726 \times {10^{ - 27}} + 16 \times 1,6748 \times {10^{ - 27}} + 16 \times 9,1094 \times {10^{ - 31}}\\
\,\,\,\,\,\,\,\,\, = 5,357 \times {10^{ - 26}}kg\\
\text{Mà }1dvC = 1,6 \times {10^{ - 27}}kg\\
\Rightarrow {M_S} = \dfrac{{5,357 \times {{10}^{ - 26}}}}{{1,66 \times {{10}^{ - 27}}}} = 32dvC\\
b)\\
{M_{Na}} = {p_{Na}} \times {m_p} + {n_{Na}} \times {m_S} + {e_{Na}} \times {m_e}\\
\,\,\,\,\,\,\,\,\, = 11 \times 1,6726 \times {10^{ - 27}} + 12 \times 1,6748 \times {10^{ - 27}} + 11 \times 9,1094 \times {10^{ - 31}}\\
\,\,\,\,\,\,\,\,\, = 3,85 \times {10^{ - 26}}kg\\
\text{Mà }1dvC = 1,6 \times {10^{ - 27}}kg\\
\Rightarrow {M_{Na}} = \dfrac{{3,85 \times {{10}^{ - 26}}}}{{1,66 \times {{10}^{ - 27}}}} = 23dvC
\end{array}\)