Answer:
Because Greenhouse gases let the sun's light shine onto the Earth's surface, but they trap the heat that reflects back up into the atmosphere. And this way, they act like the glass walls of a greenhouse. This greenhouse effect also keeps the Earth warm enough to sustain life.
Explanation:
I dont know the answer but i have some explanation for that question.
Since krypton is in the far right row of the periodic table, its outermost shell is full with eight electrons. This is one of the happy elements and has an electron configuration of 2-8-18-8.
Answer is: D. Cl (chlorine).
The ionization energy (Ei) is the minimum amount of energy required to remove the valence electron, when element lose electrons, oxidation number of element grows (oxidation process).
Barium, potassium and arsenic are metals (easily lost valence electrons), chlorine is nonmetal (easily gain electrons).
Alkaline metals (in this example, potassium) have lowest ionizations energy and easy remove valence electrons (one electron), earth alkaline metals (in this example, barium) have higher ionization energy than alkaline metals, because they have two valence electrons.
Nonmetals (in this example chlorine) are far right in the main group and they have highest ionization energy, because they have many valence electrons.
Transition metals will often violate the octet rule by using their d orbitals for bonding.
