vahid zaker airat, radio and television news agency. the chemical machine competition is an interesting and exciting competition in which chemical machines made by groups compete. these machines need the help of chemicals to move. reporter. we went to a group of students who won the second place in this competition. chemical car racing is a competition in which the driving force and braking of these cars are one it is a chemical reaction. recently, a group from iran participated in this competition in india. there are competitions that are held every year at the world level by various scientific associations and the purpose of holding the competition. it gives us oxygen and water . we put the oxygen gas that is produced from this reaction into a pneumatic piston and it disconnects the batteries and brakes the car. when the oxygen gas is produced inside the reactor, this oxygen gas enters a pneumatic jack and he moves the piston , hits the button to disconnect the battery and the car stops to calculate the movement and braking in time fo