I believe the correct response is A. At higher elevations it would take less time to hard boil an egg, because there is less atmospheric pressure.
All of the above!
By analyzing the remains of fossilized organisms (such as old animal bones or plants), scientists can approximate what the organism might have looked like and the climate/environment it lived in -- and based on that, they can try to figure out how the Earth's surface has changed over time. Also, they can use the fossil to compare it to creatures that live now to see what has changed in that species over time.
Answer:
See explanation
Explanation:
If we look at the models, we will see that the three fluorine atoms in CF3COOH are attached to the carbon that is next to the -COOH group.
As a result of the electron withdrawing effect of the three fluorine atoms, CF3COOH is much more acidic (104 times more acidic) than CH3COOH. This is reflected in the value of the Ka for each acid.
This electron withdrawing effect of the three fluorine atoms also stabilizes CF3COO- much more than CH3COO-.
Mixtures are combinations of materials that can be separated by in most cases time. For instance, oil and water is a mixture. You can tell this by placing the two chemicals in a container and shaking them. They will mix and look like one substance, however, they will separate into the two liquids after some time is given. Assuming that "pure substance" is a solution, a substance is similar to a mixture, but the materials used in the solution are not separable. Over time the materials in the containing will not separate. I believe this is the answer you are looking for.