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.
Answer: C
Explanation:
Hot air is a lot less dense for a few reasons. Hot air essentially means the particles have more kinetic energy, and move around a lot more. Cold air is dense because the particles move a lot less, have less energy, and are closer together.
If an organism is heterozygous, it has one copy of two different alleles. If an organism is homozygous, it has two copies of the same allele.
Correct answer: B. Paleozoic. I took the test and it was right.
Answer: Cells from the smallest to the largest of mammals often seem to be “one size fits all.” Now a closer look reveals that whether a cell lives in an elephant, mouse or something in between can make a big difference in its life
Explanation:
