A general view about the ionic and covalent molecules is that they do not react with each other. Surprisingly, vinegar which has covalent bond but still it is miscible in water which is an ionic compound. The reason of the solubility of vinegar in water is that vinegar is an acid which is produced from acetic acid CH3COOH. Therefore, the ionic component of acetic acid is dissolved in water and that's why vinegar is soluble in water.
