What happened when you bituminous coal and vinegar?

When you mix bituminous coal and vinegar, a chemical reaction does not occur because vinegar (acetic acid) is not a strong enough acid to react significantly with the carbon in coal. However, the vinegar can help to clean the coal's surface by dissolving some impurities and minerals. This mixture may also create a slight effervescence if any carbonate minerals are present in the coal, but the primary components of coal remain unaffected. Overall, the interaction is minimal and primarily physical rather than chemical.