Question

consider the reaction of 75.0 ml of 0.350 m c₅h₅n (kb = 1.7 x 10⁻⁹) with 100.0 ml of 0.425 m hcl.
how many moles of h⁺ is present in 100.0 ml of hcl solution?

Explanation:

Step1: Convert volume to liters

Since \(1\space L = 1000\space mL\), then \(V = 100.0\space mL=\frac{100.0}{1000}\space L = 0.1000\space L\)

Step2: Use the formula \(n = C\times V\)

The concentration of \(HCl\) is \(C = 0.425\space M\) (moles per liter). The formula for the number of moles \(n\) of a solute is \(n = C\times V\), where \(C\) is the molarity and \(V\) is the volume in liters. For \(HCl\), which is a strong acid and dissociates completely as \(HCl
ightarrow H^{+}+Cl^{-}\), the number of moles of \(H^{+}\) is equal to the number of moles of \(HCl\). So \(n_{H^{+}}=n_{HCl}\)
Substitute \(C = 0.425\space M\) and \(V=0.1000\space L\) into \(n = C\times V\)
\(n_{H^{+}}=0.425\space mol/L\times0.1000\space L\)

Answer:

\(0.0425\space mol\)