Properties of Hydrogen

Hydrogen is a gas at room temperature, and is the first element in the periodic table. It has the chemical symbol H, but is usually found as a diatomic molecule of H2. It reacts with oxygen to form water. Hydrogen is a colourless, odourless gas that burns and can form an explosive mixture with air. It is the least dense gas known to man. A jet of hydrogen burns in air with a very hot blue flame. Hydrogen is the most abundant element in the universe. It is found most abundantly on Earth in water, but can also be found in the atmosphere in very small amounts. When reactive metals like sodium come into contact with water Hydrogen gas is released. The test for hydrogen is that when a test tube containing hydrogen is placed near a flame it ignites with a “ squeaky Pop”. All metals above Hydrogen in the reactivity series react with acids to displace hydrogen. Hydrogen combines with nitrogen to form ammonia.