Helium has two valence electrons. As an element, helium is very stable and contains a single s-orbital on its outer shell.Know More
Helium is the periodic table's least reactive element, and it sits at the top of the noble gas group. In addition to being monoatomic, it has a low boiling point and is the second most common gas in the universe. It is small, light and does not react with any other elements. Helium has the following characteristics:
Helium's electron configuration is 1s^2. It has seven isotopes, and two of them are liquid. Its electron affinity is 0 kJ/mol and it has an atomic radius of 31 pm.
Natural gas deposits contain 10 percent helium, which makes them an excellent resource for extracting it. People extracting helium can obtain it from sources in Russia, Texas, Poland, Algeria, China and Canada. When liquefied, it can be used to freeze biological materials for later use. In addition, scuba divers use air that is a blend of helium and oxygen for underwater breathing. Finally, people can use helium in balloons to make them float.Learn more about Atoms & Molecules
Zirconium has four valance electrons, with two in the 4d level and two in the 5s level. This allows it to combine with other elements and ions in different configurations. It has valence charges of +2, +3 and +4.Full Answer >
Chromium has six valence electrons. The atomic number of chromium is 24, and its electron configuration is 1s22s2 2p63s23p63d54s1 or 2, 8, 13, 1 electrons per shell. The electrons in the 3d54s1 shells form the valence electrons as the five electrons in the 3d shell participate in chemical bond formation.Full Answer >
An atom of boron has three valence electrons. The valence electrons of boron occupy the second orbit around the nucleus of the boron atom. Thus, the boron atom has an electronic configuration of [He] 2s2 2p1.Full Answer >
Oxygen has six valence electrons and is assigned a valence number of 2. This means it needs two electrons to satisfy its bonding requirements. When these two electrons come from two hydrogen atoms, the three atoms together form H2O, which is water.Full Answer >