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Step 1: Calculate the moles of Calcium (Ca)
The molar mass of Ca is 40 g/mol.
Moles of Ca = Mass of Ca / Molar mass of Ca = 14 g / 40 g/mol = 0.35 mol
Step 2: Determine the moles of $CaCl_2$ and $H_2$ produced
From the balanced equation, $Ca + 2HCl \rightarrow CaCl_2 + H_2$, 1 mole of Ca produces 1 mole of $CaCl_2$ and 1 mole of $H_2$.
Therefore, 0.35 mol of Ca will produce 0.35 mol of $CaCl_2$ and 0.35 mol of $H_2$.
Step 3: Calculate the mass of $CaCl_2$ produced
The molar mass of $CaCl_2$ is 40 + 2(35.5) = 40 + 71 = 111 g/mol.
Mass of $CaCl_2$ = Moles of $CaCl_2$ * Molar mass of $CaCl_2$ = 0.35 mol * 111 g/mol = 38.85 g
Step 4: Calculate the volume of $H_2$ produced at STP
At STP, 1 mole of any gas occupies 22.4 L.
Volume of $H_2$ = Moles of $H_2$ * 22.4 L/mol = 0.35 mol * 22.4 L/mol = 7.84 L
Step 5: Analyze the options
Correct Answer: D