To calculate the molar mass of XOH, we need information about the concentrations and volumes involved in the titration. Since these are not provided in the current image, we will make reasonable assum

To calculate the molar mass of XOH, we need information about the concentrations and volumes involved in the titration. Since these are not provided in the current image, we will make reasonable assumptions based on typical titration problems.

Assumptions:

• Concentration of $H_2SO_4$ (solution A) = $0.100 \text{ mol/dm}^3$.
• Volume of XOH (solution B) used in each titration = $25.00 \text{ cm}^3$.
• The average volume of $H_2SO_4$ (solution A) used from the previous step is $24.35 \text{ cm}^3$.
• Solution B was prepared by dissolving $2.72 \text{ g}$ of XOH in $250 \text{ cm}^3$ of water.

Step 1: Write the balanced chemical equation and determine the mole ratio.
The reaction between sulfuric acid ($H_2SO_4$) and a metal hydroxide (XOH) is:

$$H_2SO_4(aq) + 2XOH(aq) \rightarrow X_2SO_4(aq) + 2H_2O(l)$$

The mole ratio of $H_2SO_4 : XOH$ is $1:2$.

Step 2: Calculate the moles of $H_2SO_4$ used.
The concentration of $H_2SO_4$ (solution A) is $0.100 \text{ mol/dm}^3$.
The average volume of $H_2SO_4$ used is $24.35 \text{ cm}^3$, which is $0.02435 \text{ dm}^3$.

$$\text{Moles of } H_2SO_4 = \text{Concentration} \times \text{Volume}$$ $$Moles of H_2SO_4 = 0.100 mol/dm^3 \times 0.0243$$