Test: Hydrogen & Hydrides

Sum of number of neutrons and protons represents mass number. Tritium has 1 proton and 2 neutrons. 

A small and highly electronegativity elements form a stronger hydrogen bond. The order of size of N , O and F is F < O < N .and so the order of strength of hydrogen bond is F > O > N.

Hence, electronegativity of F is the highest, therefore magnitude of positive charge on hydrogen and negative charge on F is the highest in HF and Hence, electrostatic attraction of H bonding is the strongest in HF.

Hydrides are classified into three major groups, depending on what elements the hydrogen bonds to. The three major groups are covalent, ionic, and metallic hydrides. Formally, hydride is known as the negative ion of a hydrogen, H-, also called a hydride ion.

Isotopes of an element have the same number of electrons. They have the same electronic distribution in various orbitals around the nucleus.  They differ in the number of neutrons in the nucleus. They have the same atomic number Z and have different mass number M.

The chemical properties of an element are dependent on the electronic configuration inside the atoms. Since Isotopes have same number electrons in the same orbitals, their chemical properties remain same.

Their physical properties like color, mass, weight, density shape or state may be different from each other.

The physical properties of isotopes of the same element are not identical because the atomic mass and mass number differ. This affects physical properties such as density and temperature of change of state, eg. boiling and melting point.

Zn + 2HCl ------> ZnCl₂ + H₂ since it forms 2 moles of hydrogen it is a dihydrogen.

Electron –rich hydrides, as the name suggest, are compounds of hydrogen with other elements that have excess electrons present as lone-pairs. For example ammonia –NH₃ is a hydride of nitrogen that has one lone pair, water (H₂O) is a hydride of oxygen that has two lone pairs etc.

Hydrogen has some properties, resembling with IA group elements (alkali metals) and rest resembling with halogens (VII A group elements). Tendency to gain one electron is the property of halogens. Hence, hydrogen resembles with halogens in this respect.

Ionic hydrides are commonly known as saline hydrides or pseudohalides. These compounds form between hydrogen and the most active metals, especially with the alkali and alkaline-earth metals of group one and two elements. In this group, the hydrogen acts as the hydride ion (H−).

Covalent Hydrides are formed by the p-Bolock elements. Metallic or Interstitial Hydrides are formed by many d-block and f-block elements when heated with hydrogen under pressure. The hydrides tend to be non-stoichiometric and they may be of variable composition. Others have properties between metallic and covalent.

Hydrogen is a nonmetal and is placed above group in the periodic table because it has ns¹ electron configuration like the alkali metals. However, it varies greatly from the alkali metals as it forms cations (H⁺) more reluctantly than the other alkali metals.

The concentration of deuterium relative to hydrogen is very very small. It's is much easier for a deuterium atom to come across a hydrogen atom and form HD. The probability of two D coming together to form D₂ is lower. This may be the cause of most deuterium not only on earth but the entire universe to be present as HD.

Heavy water (D₂O), also called deuterium oxide, water composed of deuterium, the hydrogen isotope with a mass double that of ordinary hydrogen, and oxygen.

Hydrogen has electronic configuration 1s Its electronic configuration is similar to the outer electronic configuration (ns) of alkali metals, which belong to the first group of the periodic table. Hydrogen therefore has resemblance to alkali metals, which lose one electron to form unipositive ions. Like alkali metals, hydrogen forms oxides, halides and sulphides.

Dihydrogen is the most abundant element in the universe (70% of the total mass of the universe) and is the principal element in the solar atmosphere. The giant planets Jupiter and Saturn consist mostly of hydrogen. However, due to its light nature, it is much less abundant (0.15% by mass) in the earth's atmosphere.

hydrogen, also known as hydrogen-3) is a radioactive isotope ofhydrogen. The nucleus of tritium (sometimes called a triton) contains one proton and two neutrons, whereas the nucleus of protium (by far the most abundant hydrogenisotope) contains one proton and no neutrons.

Tritium is the most stable radioisotope ofhydrogen. That is, of all radioactive isotopes of hydrogen, tritium is the leastradioactive. Scientists had created four other radioactive hydrogen isotopes, but these isotopes are very unstable and does not exist naturally.

Tritium is an isotope of Hydrogen with atomic mass of 3 amu. This means it should have 3 nucleons. Therefore sum of no. of proton and neutron in Tritium is 3.

Dinitrogen and dihydrogen react with each other to produce ammonia according to the following chemical equation: N2(g)+H2(g)→2NH3(g)

The noble gases are the chemical elements in group 18 of the periodic table. They are the most stable due to having the maximum number of valence electrons their outer shell can hold. Therefore, they rarely react with other elements since they are already stable.