An acid is a substance that gives up positively charged hydrogen ions (H⁺) when dissolved in water. A base (alkaline) gives up negatively charged hydroxide ions (OH^-) when dissolved in water. pH is a scale that measures of how basic or acidic a solution is. Numbered from 0 to 14, solutions with a pH of 7 are neutral, less than 7 are acidic, more than 7 are alkaline.

Carbohydrates are major sources of energy for the body and are found in sugars (fruit, cane sugar, beets) and starches (bread, rice, potatoes, pasta).

An element is matter than cannot be separated into different types of matter by ordinary chemical methods.

Force is applied to change an object's speed or direction of motion.

Found in both animal sources (meat, fish, eggs, cheese) and vegetables (beans, nuts, some grains), proteins are important for the body's maintenance, growth, and repair.