As you can see in the picture we have +ΔH so that means for this reaction we need to GET heat. so the answer is A. endothermic :))
i hope this is helpful
have a nice day
Answer:
Hydrogen
Explanation:
It is considered a special element due to its flexibility in giving up & taking in electrons, therefore making it good for organic & inorganic chemistry. Hydrogen has only one proton and one electron and is the only element which has no neutrons. it is considered as the simplest element in the universe and gives a valid reason for it to be the most abundant and common element in the universe.
Hoped this helped! If this doesn't fit your 80 word count, you could shorten it.
Answer:
Carbon has 4 valence electrons (electrons that are used in bonding), and therefore it can make 4 bonds which is the most one can (other than some exceptions, but in general it is the most). It wants to make 4 bonds so it can reach a full octet of 8 elections, hence the rule of 8.
Explanation:
The answer is B. This is because Sodium has 1 valence electron and Fluorine has 7 valence electrons. All elements want 8 valence electrons so they may be stale, like the noble gases are. Hope this helps.
The two compounds present
in unpolluted air are carbon dioxide and water. You may think that carbn
dioxide is a greenhouse gas, yes it is and at the same time not. There animals
in the earth that produces carbon dioxide into the atmosphere, the carbon
dioxide too, is also need for plan respiration.
