Cinnamic acid is an organic acid separated from cinnamon bark or benzoin. It can be dissolved in benzene, ether, etc. in any proportion. In addition, sodium cinnamate is easily soluble in hot water and slightly soluble in ethanol. Therefore, there is no fixed requirement for the solubility of the two. However, depending on the use situation, the solubility of cinnamic acid and sodium cinnamate is generally that one gram can be dissolved in 2 liters of water (2.5 degrees Celsius).