D: After they emit light, electrons are sucked into the nucleus of the atom.
Answer:
When atoms join together to form molecules, they are held together by chemical bonds. These bonds form as a result of the sharing or exchange of electrons between the atoms. It is only the electrons in the outermost shell that ever get involved in bonding.
The answer is 40.
We can solve this by finding out the number of protons, and neutrons. Atomic number of an element means the number of protons in that element. So, the atom has 30 protons if the atomic number is 30.
On the other hand, mass number is the total number of protons and neutrons, but not electrons, because they're too light comparing to the other 2. Therefore, we can simply solve the number of neutrons in the atom by subtracting the number of protons from the mass number. 70 - 30 = 40.
Therfore, the number of neutrons is 40.
Answer:
"The elements are arranged in seven horizontal rows,called periods or series,and 18 vertical columns,called Groups."
Explanation:
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