According to the valence shell electron pair repulsion (VSPER) theory, an ammonia molecule <span> has a </span>trigonal pyramidal<span> shape with an experimental bond angle measure of 106.7 degrees. This is why it is difficult to accurately represent ammonia two-dimensionally because the molecular structure entails a 3-D projection with angles in it unlike the linear structure.</span>
Answer:
In short, because we are tearing up the oxygen factories to make way for carbon dioxide emitters. (Doesn't make a lot of sense, read the explanation)
Explanation:
So, 1000 years ago, we had a lot more trees, didn't have engines or cars or factories or anything, really that released carbon dioxide into the air and we had a lot more trees and since the invention of cars, engines, carbon dioxide-emitting tools and factories and all the other things that emit "Greenhouse gases" and in doing that, cleared more trees to make room for factories and roads and that has drastically changed the outlook of the carbon cycle.
The reaction of iron sulfide (FeS) with hydrochloric acid (HCl) results in the formation of ferrous chloride (FeCl2) and hydrogen sulfide (H2S) gas. The reaction can be shown as follows:
FeS (s) + HCl(aq) ---- FeCl2(s) + H2S(g)
The bubbles indicate the formation of H2S gas which is a chemical change. The formation of bubbles indicates this change as it suggests that the reactants are combing to form products i.e. it signals a chemical reaction.
The kinetic energy of an object increases when heat is added.
Answer:
The immune system responds to antigens by producing cells that directly attack the pathogen, or by producing special proteins called antibodies. Antibodies attach to an antigen and attract cells that will engulf and destroy the pathogen. The main cells of the immune system are lymphocytes known as B cells and T cells.
