1) An antacid is a substance which neutralizes stomach acidity and is USED to relieve heartburn, indigestion or an upset stomach. Some antacids have been used in the treatment of constipation and diarrhea. Currently marketed antacids contain salts of aluminum, calcium, magnesium, or sodium.2) respiration is the movement of OXYGEN from the outside environment to the cells within tissues, and the removal of carbon dioxide in the opposite direction. 3) motion is the phenomenon in which an object changes its position over time. Motion is mathematically described in terms of displacement, DISTANCE, velocity, acceleration, speed, and time.4) Speed can be thought of as the rate at which an object covers distance. A fast-moving object has a high speed and covers a relatively large distance in a given amount of time, while a slow-moving object covers a relatively SMALL amount of distance in the same amount of time.5) A pH indicator is a halochromic chemical compound added in small amounts to a SOLUTION so the pH of the solution can be determined visually. Hence, a pH indicator is a chemical detector for hydronium ions or hydrogen ions in the Arrhenius modelExplanation: mark me as brainlist