Pure metals with nearly the same elastic properties as hard, covalent ceramics are often very soft, even at low temperatures. Why the difference? "Directed bonds" is the common answer. Or, "the Peierls-Nabarro stress is large". However, the former is only qualitative, while the latter does...
I Am The Reason Why Rubies Are Red And Emeralds Are Green. Who Am I? I Have One Of The Highest Melting Points Of All Pure Elements, With Only Tantalum And Tungsten Surpassing Me. Who Am I? Conclusion Metals such as sodium, potassium and magnesium (among many ot...
Are alkali metals soft or hard? The alkali metals are solids at room temperature (except for hydrogen), but have fairly low melting points: lithium melts at 181ºC, sodium at 98ºC, potassium at 63ºC, rubidium at 39ºC, and cesium at 28ºC. They are alsorelatively soft metal...
and some other countries, karat only measures the purity of gold: 24-karat gold is pure gold, but usually you mix gold with other metals like copper or silver to make jewelry (because pure gold is too soft). Each karat indicates 1/24 of the whole. So, if a piece of jewelry is ...
Chemically speaking, gold is a transition metal. Transition metals are unique,because they can bond with other elements using not just their outermost shell of electrons(the negatively charged particles that whirl around the nucleus), but also the outermost two shells. ...
Why do molten metals oxidize? Why is erosion generally considered a destructive process? Why are some alcohols soluble in water? Why are coral reefs considered delicate? What are the properties that influence the acidity of a substance?
Why do you think metals usually have higher densities than other materials? Explain why all of a pure solution does not vaporize at once when the boiling point is reached. What are the physical properties of pure iron? Why is Ni not considered metal even though it composes over 2% of t...
Conversion coatings are the modified surfaces of metal resulting from specific chemical treatment. These conversion coatings, which can be on steel, aluminum, or most other metals, typically include zinc, manganese, and iron phosphates or chromates. The principle function of these coatings is to imp...
Systems with such non-trivial similarities are generally referred to as 'quasi-universal'. From the fact that the exponentially repulsive pair potential has strong virial potential-energy correlations in the low-temperature part of its thermodynamic phase diagram, we here show that a liquid is ...
Thiols, once known as mercaptans, are a family of organic chemicals that contain sulphur. ... Many thiols have strong and repulsive odours.In their pure forms, some thiols are flammable. Thiols are commonly added to natural gas so that people can smell the gas in case of a leak. ...