| Time (s) | 0 | 10 | 20 | 30 | 40 | 50 |
| Mass of reaction mixture (g) | 65/98 | 65/32 | 64/88 | 64/66 | 64/55 | 64/50 |
| Mass of carbon dioxide (g) | 0 | 0/66 | 1/10 | \ldots | \ldots | \ldots |
| Time (s) | $n(\mathrm{CO_2})$, (mol) | $\Delta n(\mathrm{CO_2})$, (mol) | $\bar{R}(\mathrm{CO_2}) = \dfrac{\Delta n(\mathrm{CO_2})}{\Delta t}$, $(\mathrm{mol.s^{-1}})$ |
| 0 | 0 | ||
| 10 | $1/5\times10^{-2}$ | $1/5\times10^{-2}$ | $1/50\times10^{-3}$ |
| 20 | $2/5\times10^{-2}$ | $1/00\times10^{-2}$ | $1/00\times10^{-3}$ |
| 30 | \ldots | ....a.... | \ldots\ldots\ldots |
| 40 | \ldots | \ldots\ldots\ldots | ....b.... |
| 50 | \ldots | ....c.... | \ldots\ldots\ldots |
\textbf{223-} Considering the data in the tables below regarding the changes in amount and concentration of $\mathrm{CO_2}$ gas over time in the reaction:
$$\mathrm{CaCO_3(s) + 2HCl(aq) \rightarrow CaCl_2(aq) + CO_2(g) + H_2O(l)}$$
which shows c with respect to a, what are the values of a and b in how many moles per second? (Read the options from right to left, $\mathrm{CO_2 = 44\ g.mol^{-1}}$)
\begin{center}
\begin{tabular}{|c|c|c|c|c|c|c|}
\hline
\textbf{Time (s)} & 0 & 10 & 20 & 30 & 40 & 50 \\
\hline
\textbf{Mass of reaction mixture (g)} & 65/98 & 65/32 & 64/88 & 64/66 & 64/55 & 64/50 \\
\hline
\textbf{Mass of carbon dioxide (g)} & 0 & 0/66 & 1/10 & \ldots & \ldots & \ldots \\
\hline
\end{tabular}
\end{center}
\begin{center}
\begin{tabular}{|c|c|c|c|}
\hline
\textbf{Time (s)} & $n(\mathrm{CO_2})$, (mol) & $\Delta n(\mathrm{CO_2})$, (mol) & $\bar{R}(\mathrm{CO_2}) = \dfrac{\Delta n(\mathrm{CO_2})}{\Delta t}$, $(\mathrm{mol.s^{-1}})$ \\
\hline
0 & 0 & & \\
\hline
10 & $1/5\times10^{-2}$ & $1/5\times10^{-2}$ & $1/50\times10^{-3}$ \\
\hline
20 & $2/5\times10^{-2}$ & $1/00\times10^{-2}$ & $1/00\times10^{-3}$ \\
\hline
30 & \ldots & \textbf{....a....} & \ldots\ldots\ldots \\
\hline
40 & \ldots & \ldots\ldots\ldots & \textbf{....b....} \\
\hline
50 & \ldots & \textbf{....c....} & \ldots\ldots\ldots \\
\hline
\end{tabular}
\end{center}
\begin{center}
(1) $4/3\times10^{-3}$ , $0/22$ \hspace{2cm} (2) $2\times10^{-3}$ , $0/55$
(3) $2/5\times10^{-4}$ , $0/22$ \hspace{2cm} (4) $2\times10^{-4}$ , $0/55$
\end{center}