What is hydrogen gas?
Hydrogen is the first element of periodic table and is a colorless, odorless and an insipid gas that is formed by the diatomic molecule H2. Hydrogen (H) is a lightest chemical element. The atomic number of hydrogen is 1 and it has no neutron thus its mass number is also 1. It is the most abundant element found in this universe. Maximum part of this universe is taken by hydrogen in various forms like planets are composed of only hydrogen. Water (H2O): the main source of life, without which there can be no living being, is also composed of hydrogen and oxygen. Hydrogen present in water keeps the body cells hydrated and helps to remove toxins from the body. Hydrogen is present in all proteins, sugars, fats and starch, which all are very vital for human diet. Hydrogen helps to slow down aging process as stored hydrogen in tissues of the body protects us from that damage which radicals can do.
Why H+ is often called a proton?
Oxidation of hydrogen causes the removal of electron due to which it becomes an ion: H+. This ion has no electron as it has lost its single electron so it just consists of a proton inside its nucleus. This is the reason due to which H+ is named as a proton.
Properties of hydrogen
Hydrogen is most flammable as compared to all known substances. It is highly soluble in organic substance as compared to water, even many metals have ability to absorb hydrogen as well. For example, when steel absorbs hydrogen, it becomes brittle. Instead of normal temperature, Hydrogen is highly reactive at higher temperatures. Generally, it is in diatomic form which dissociates into single atoms (H) at higher temperatures, which is actually very powerful reductive agent. Hydrogen can produce free metals by reacting with their chlorides or oxides (usually copper, lead, silver, bismuth etc). when atomic hydrogen reacts with oxygen it results in the production of hydrogen peroxide (H2O2). If hydrogen is heated then it can cause violent combustion or even explosion.
Hydrogen exposure results in many health risks like high concentration of hydrogen can cause oxygen deficiency. If one breaths in such environment, he will experience headache, ringing in ears, drowsiness nausea, dizziness, vomiting, and even depression. Hydrogen exposure also affects the skin by changing its color into blue. These all include in hazards of hydrogen gas.
There are five states of hydrogen: gaseous, liquid hydrogen, slush hydrogen, solid hydrogen and metallic hydrogen.
- Naturally, hydrogen is found in gaseous sate as H2.
- To get liquid hydrogen, it is cooled below its critical temperature that is 33 K. However, hydrogen is cooled to 20 K for making it permanently in liquid state at standard atmospheric pressure.
- 3rdly, slush hydrogen is the mixture of solid and liquid hydrogen at triplet point, with low temperature and high density than that of liquid hydrogen.
- Solid hydrogen is obtained by reducing the temperature of hydrogen below its melting point 14 K. Metallic hydrogen is a hydrogen phase in which it acts like an electrical conductor.
Hydrogen forms compounds with various elements even it is not too reactive under standard conditions. Usually, it forms compound with those atoms which are more electronegative like halogens (F, Cl, Br, I or O). Such bonding is termed as hydrogen bonding. When hydrogen makes compounds with less electronegative (more electropositive) atoms like metals and metalloids, hydrogen takes partial negative charge. Such compounds are called hydrides. When hydrogen makes compounds with carbon, the products are termed as hydrocarbons (which is actually a sub term of organic compounds).
Isotopes of hydrogen
There are 3 isotopes of hydrogen: 1H1 (protium), 1H2 (deuterium), 1H3 (tritium). Protium is a stable isotope which is abundant in nature, consisting of 1 proton only whereas, deuterium has 1 proton and 1 neutron. It is considered that all the deuterium has been formed by the time of big bang. Deuterium is also a stable isotope of hydrogen. However, the water that is enriched with deuterium than protium (normal water) is called heavy water. Heavy water is not good for many purposes like drinking and washing but it has many uses too, like it is used as potential fuel in nuclear fusion and as neutron moderator and coolant in nuclear reactors.
On the other side, tritium: containing 1 proton and 2 neutrons, is radioactive as it decays by beta decay into 2He3. It is used in luminous painting of watches. However, glass prevents radiations to come out. Interaction of cosmic rays and atmospheric gases produce small amounts of tritium. Tritium is used in production of atomic bomb as it is radioactive. Of these 3 isotopes of hydrogen, protium is abundant as it covers 99% of the universe, 2ndly deuterium takes 0.015% and lastly tritium is found in very small quantities and is mostly produced by artificial ways. Overall, hydrogen takes 0.15% of earth’s crust.
Is hydrogen soluble in water?
Water is a polar compound, whereas hydrogen is non-polar. Water contains hydrogen atoms and oxygen atoms. In water, hydrogen is only sparingly soluble. In practice, hydrogen has little to no solubility in water. However, hydrogen is able to get dissolved in various transition metals, rare earth metals, both non-crystalline and amorphous metals. Solubility of hydrogen in metals is affected by the impurities in crystal lattice.
Is hydrogen gas flammable?
The answer is yes, it is highly flammable, but there are a few points to clarify. When hydrogen is said to be flammable, it does not refer to the elemental form of hydrogen. The diatomic hydrogen gas is the most flammable. Many flammable substances require a high concentration to combust or catch fire, but this is not the case with hydrogen. Hydrogen will combust at concentrations ranging from 4% to 75%.
Why hydrogen has many spectral lines?
Although a hydrogen atom has only one electron, it contains a large number of shells, so a photon is released as this single electron jumps from one shell to another and the energy difference between the shells causes the release of various wavelengths. This is the reason due to which there are several spectral lines of mono-electronic hydrogen.
Uses of hydrogen gas
Hydrogen has many uses, from which the top one is the synthesis of ammonia. It is also used to refine fuel like hydrocracking and sulfur elimination. Catalytic hydrogenation of unsaturated vegetable oils consumes huge quantity of hydrogen to get solid fat. With a combination of oxygen, hydrogen is being used as rocket fuel. Hydrogen can be converted to or from electricity from bio-fuels, from and into natural gas and diesel fuel, theoretically with no emissions of either CO2 or toxic chemicals. When hydrogen atoms join each other to form hydrogen molecules, then heat is released, which is used for getting high temperatures in atomic hydrogen welding.