Volume percent is a way to express the concentration of a substance in a mixture. It is calculated by taking the volume of the substance and dividing it by the total volume of the mixture, then multiplying by 100. For example, if you have 30 milliliters of water mixed with 70 milliliters of alcohol, the volume percent of alcohol would be (70 / 100) × 100 = 70%. This measurement is commonly used in chemistry and various industries to describe solutions and mixtures. It helps in understanding how much of a particular component is present in relation to the total volume, which is essential for tasks like dilution and formulation.