Hydrogen and Oxygen Information and Uses Unit 2 - Mission to Mars Connection

Hydrogen is the lightest and most abundant element in our universe.

Hydrogen does not exist by itself in nature Hydrogen exists as parts of compounds Hydrogen is part of many compounds such as the compounds that make up: Fossil fuels(oil, coal, natural gas) plants water

Uses for hydrogen Thermonuclear energy ( Sun) A lifting agent (Hindenberg blimp) Fuel Cars Rocket fuel

Oxygen Oxygen is a tasteless gas. It has no smell or color. It is the 3 rd most abundant element in the universe It comprises 22% of the air we breathe This element is found in the human body, the Sun, oceans and the atmosphere. Without oxygen, humans will not be able to survive.

Uses for Oxygen Of all the uses of oxygen, sustaining life is the most important. Oxygen is needed by all living organisms. Through a process known as aerobic respiration, energy from food is generated. This allows humans and animals to perform their daily activities.

Water (H 2 O) Water is the most abundant compound on Earth It is made up of 2 hydrogen atoms and 1 oxygen atom that are chemically bonded together The ratio of hydrogen to oxygen is 2:1 which means there is twice as much hydrogen as oxygen

A water molecule is made up of one oxygen atom sharing electrons with two hydrogen atoms.

Water A water molecule is formed by two elements: two positive Hydrogen ions and one negative Oxygen ion. The water molecule is held together by the electromagnetic attraction between these ions.

Water exists as a compound so it can not be separated by physical means Hydrogen and oxygen can be separated from water by electrolysis

Electrolysis Electrolysis is a method of using a direct electric current (DC) to drive an otherwise non-spontaneous chemical reaction.

Electrolysis When electricity is introduced to water through two electrodes, a cathode (negative) and an anode (positive), these ions are attracted to the opposite charged electrode. The positively charged hydrogen ions will collect on the cathode and the negatively charged oxygen will collect on the anode.

Electrolysis When these ions come into contact with their respective electrodes they either gain or lose electrons depending on their ionic charge. In this case the hydrogen gains electrons and the oxygen loses them In doing so these ions balance their charges, and become real, electrically balanced, bona fide atoms (or in the case of the hydrogen, H 2, a molecule).

Electrolytes Pure water itself is not a good conductor of electricity, so in our experiment baking soda will be added to make the solution an electrolyte. An electrolyte is a part of a solution that can be broken up by electrolysis. Electro refers to energy and electricity and - lysis refers to splitting apart.

Diagram of Electrolysis Set up