1. Why is the ionization energy of helium greater than that of the other elements?Although fluorine is the most electronegative element, silicon tetrafluoride (SiF_4) does not have-a dipole moment. Explain.What is a covalent bond? What type of substances form covalent bonds?What is an electri...
What is the Lewis structure of the Pb^{2+} ion? What is a suitable Lewis structure for Li_2S? Will it have two lithium ions each with a (+1) charge and one sulfide ion with four pairs of electrons and a (-2) charge? What is the Lewis dot structure for gallium?
Semiconductor materials include – Silicon,antimony, arsenic, boron, carbon, germanium, gallium arsenide, selenium, silicon carbide, sulfur, tellurium, oxides of most metals. What is Superconductor? Superconductor is an element, inter-metallic alloy, or a compound that conducts electricity without resist...
Before it restricted the flow of these materials, China accounted for more than half of US imports of gallium and germanium,accordingto the US Geological Survey. Together, China and Russiacontrol 50%of the worldwide reserves of antimony.
it fails for the SeCl62− and the TeCl62− ion, which have a regular octahedral structure). (ii) When we use differences in electronegativity to gauge the ionic character of bonds, we should remember that this does not always work (e.g. caesium is more electropositive than lithium,...
Chemistry is the branch which deals with the detailed study of matter, its properties, how and why atoms/substanced combine or separate to form other substances. Understand all the basic concepts of Organic, Inorganic, and Physical Chemistry with detaile
There can be material substitution (material x against material y) or technological substitution, switching to an alternative technology which requires different raw materials (Schebek and Becker2014). The competition between silicon photovoltaic cells against CIGS (copper-indium-gallium-diselenide) or cad...
To form scanning ion images by collecting the secondary electrons (SE) generated by the interaction of the incident ions and the sample surface. To locally sputter the material surface to directly fabricate arbitrary nanostructures.The most commercially available FIB systems are using gallium (Ga) ...
According to previous findings, conventional optical orientation sensors are not able to reliably measure the orientation of gallium wafers. The different orientation of the wafer suggests that the material that adheres to its surface must be reconstructed in different orientations. Accordingly, we are...
Some substances used in the production of blue lasers include helium-cadmium gas, argon-ion gas, gallium nitride, etc. They can also be produced using infrared lasers or diode-pumped solid-state lasers. The most commonly used blue lasers are gallium nitride lasers. Blue lasers are used in ...