Answer:
1280J are required.
Explanation:
Heat of fusion is defined as the amount of heat required to change its state from liquid to solid at its melting point at constant pressure.
As heat of fusion of gold is 64J/g, there are required 64J to melt 1g of gold at its melting point. The energy required to melt 20g is:
20g * (64J/g) =
1280J are required
Answer:
Iodine. The reaction between hot iron and iodine vapor produces gray iron(II) iodide, and is much less vigorous. This reaction, the equation for which is given below, is difficult to carry out because he product is always contaminated with iodine. Iodine is only capable of oxidizing iron to the +2 oxidation state.
The answer is .......
<span>A.Nitrogen from the atmosphere is used and replaced directly by plants on the surface.
</span>
hope it helps yall!
have a great one! :)
Filtration
distillation
crystallization
chromatography
Answer:
B.) An atom of arsenic has one more valence electron and more electron shells than an atom of silicon, so the conductivity decreases because the arsenic atom loses the electron.
Explanation:
Silicon is located in the 3rd row and 14th column in the periodic table. Arsenic is located in the 4th row and 15th column in the periodic table. This means that arsenic has one more valence electron than silicon. Since arsenic is located one row down from silicon, its valence electrons occupy higher energy orbitals.
Silicon maintains a crystal-like lattice structure. Each silicon atom is covalently connected to assume this shape. When silicon gains one extra electron from arsenic, it experiences n-type doping. This new electron is not tightly bound in the lattice structure. This allows it to move more freely and conduct more electricity. This can also be explained using band gaps. Silicon, which previously had an empty conduction band, now has one electron in this band. This lowers the band gap between the conduction and valence bands and increases conductivity.