Question

which of the following is a possible way to describe the hcl component in the reaction below? 2hcl(aq) + ca(oh)₂(aq) → 2h₂o(l) + cacl₂(aq) 36.45 g hcl 2 moles hcl 2 l hcl 2 atoms hcl

Explanation:

Step1: Analyze the reaction equation

The balanced chemical equation is \(2HCl(aq)+Ca(OH)_2(aq)\to2H_2O(l)+CaCl_2(aq)\). In a balanced chemical equation, the coefficients represent the number of moles of each reactant and product.

Step2: Check each option

• For the option \(36.45\ g\ HCl\): The molar mass of \(HCl\) is \(M = 1 + 35.5=36.5\ g/mol\). The coefficient in the equation is \(2\), and \(2\ mol\ HCl\) has a mass of \(m = 2\times36.5 = 73\ g\), so this option is incorrect.
• For the option \(2\ mol\ HCl\): In the balanced chemical equation \(2HCl(aq)+Ca(OH)_2(aq)\to2H_2O(l)+CaCl_2(aq)\), the coefficient of \(HCl\) is \(2\), which means \(2\) moles of \(HCl\) are involved in the reaction.
• For the option \(2\ L\ HCl\): The coefficient in a balanced chemical equation does not represent volume directly. Volume depends on concentration (\(n = C\times V\)), and since concentration is not given, we cannot say it's \(2\ L\).
• For the option \(2\ atoms\ HCl\): \(HCl\) is a molecule. The coefficient in the equation represents the number of moles (or molecules in terms of the mole - concept, since \(1\ mol = 6.022\times10^{23}\) molecules). It does not represent the number of atoms. One \(HCl\) molecule has \(2\) atoms (\(1\) \(H\) and \(1\) \(Cl\)), but the coefficient \(2\) in \(2HCl\) represents \(2\) moles (or \(2\times6.022\times 10^{23}\) molecules) of \(HCl\).

Answer:

\(2\ moles\ HCl\)