First one because Common synthetic materials are nylon, acrylic, polyester, carbon fiber, rayon and spandex. Synthetic materials are made from chemicals and are usually based on polymers. They are stronger than natural and regenerated materials.
Answer: There are few simple rules to follow.
(1) The atomic number is equal to the number of protons.
Z
= number of protons
(2) In neutrally charged elements, the number of electrons is the same as the number of protons.
Z
= number of protons = number of electrons (no charge)
Otherwise, positive charge means that the element lost an electron and negative charge means it gained an electron.
(3) The atomic mass is equal to the sum of the number of protons and number of neutrons.
A
= number of protons + number neutrons
or
A
=
Z
+ number neutrons
So if you say that
Z
= 20 and
A
= 40, then
A
=
Z
+ number neutrons
40 = 20 + number of neutrons
40 - 20 = number of neutrons
Therefore,
number of neutrons = 20
Explanation:
Cirrhosis is liver damage that can lead to scarring and even liver failure.
Hepatitis b and c are caused by a virus, and alcoholic hepatitis is caused by drinking too much alcohol.
Answer:
The correct answer is the option c)He thought the mold had released a chemical that prevented the bacteria’s growth.
Explanation:
In the 1920s, Alexander Fleming was working in his laboratory at St. Mary's Hospital in London when, almost by accident, he discovered a naturally growing substance that could attack certain bacteria. In one of his experiments, Fleming observed that colonies of a bacterium had been depleted or removed by a mold that grew on the same Petri dish. He observed that the bacteria furthest from the fungus had grown to produce large-sized colonies, while the colonies closest to the fungus were tiny. He determined that mold made a substance that could dissolve bacteria. The fungus was penicilium chrysogenum and thus Fleming called this substance penicillin, by the name of the mold that produces it. Thus, after several years of experiments in 1930, Howard Florey and Ernest Chain developed at Oxford University the procedures to produce pure penicillin from the fungus that Fleming isolated. Thus penicillin could be concentrated by Florey and Chain, and in 1945 they shared with Fleming the Nobel Prize in Medicine.
Then, <u><em>the correct answer is the option c)He thought the mold had released a chemical that prevented the bacteria’s growth.</em></u>
