Welcome back Tina🤭🌹 — missed you this week. Step 1: Calculate the average accurate titre volume of aqueous silver nitrate ($\text{AgNO}_3$). The accurate titre readings are $30.0 \text{ cm}^3$ and $29.8 \text{ cm}^3$. $$ \text{Average titre} = \frac{30.0 \text{ cm}^3 + 29.8 \text{ cm}^3}{2} = \frac{59.8 \text{ cm}^3}{2} = 29.9 \text{ cm}^3 $$ Step 2: Fill in the blank statement. The average titre is $29.9 \text{ cm}^3$. Therefore, $\boxed{29.9}$ $\text{cm}^3$ titre (t) of aqueous silver nitrate reacts with $25.0 \text{ cm}^3$ of aqueous hydrochloric acid. Step 3: Write the balanced chemical equation for the reaction between hydrochloric acid (HCl) and silver nitrate ($\text{AgNO}_3$). The reaction is a precipitation reaction where silver ions react with chloride ions. $$ \text{AgNO}_3(\text{aq}) + \text{HCl}(\text{aq}) \longrightarrow \text{AgCl}(\text{s}) + \text{HNO}_3(\text{aq}) $$ From the equation, the mole ratio of $\text{AgNO}_3$ to HCl is $1:1$. Step 4: Calculate the moles of $\text{AgNO}_3$ used. Given concentration of $\text{AgNO}_3 = 0.1 \text{ M}$. Volume of $\text{AgNO}_3$ used (average titre) $= 29.9 \text{ cm}^3 = 29.9 \times 10^{-3} \text{ dm}^3$. $$ \text{Moles of AgNO}_3 = \text{Concentration} \times \text{Volume} $$ $$ \text{Moles of AgNO}_3 = 0.1 \text{ mol/dm}^3 \times 29.9 \times 10^{-3} \text{ dm}^3 $$ $$ \text{Moles of AgNO}_3 = 2.99 \times 10^{-3} \text{ mol} $$ Step 5: Calculate the moles of HCl reacted. Since the mole ratio of $\text{AgNO}_3 : \text{HCl}$ is $1:1$: $$ \text{Moles of HCl} = \text{Moles of AgNO}_3 = 2.99 \times 10^{-3} \text{ mol} $$ Step 6: Calculate the concentration of HCl. Volume of HCl used $= 25.0 \text{ cm}^3 = 25.0 \times 10^{-3} \text{ dm}^3$. $$ \text{Concentration of HCl} = \frac{\text{Moles of HCl}}{\text{Volume of HCl}} $$ $$ \text{Concentration of HCl} = \frac{2.99 \times 10^{-3} \text{ mol}}{25.0 \times 10^{-3} \text{ dm}^3} $$ $$ \text{Concentration of HCl} = \frac{2.99}{25.0} \text{ mol/dm}^3 $$ $$ \text{Concentration of HCl} = 0.1196 \text{ mol/dm}^3 $$ The concentration of hydrochloric acid is $\boxed{\text{0.1196 M}}$. Send me the next one 📸