Answer:
It is true that earth was once covered with oceans and little dry land.
Explanation:
Over the course of around four billion years, the Earth's oceans have lost about a quarter of their original mass. Today the atmosphere is rich in oxygen, which reacts with both hydrogen and deuterium to recreate water, which falls back to the Earth's surface. So the vast bulk of the water on Earth is held in a closed system that prevents the planet from gradually drying out. According to the researchers, the continents emerged relatively suddenly from an ocean that covered 95 percent of the Earth's surface. The appearance of large masses of dry land would have caused more extreme weather, changes in ocean currents and the emergence of proper seasons. In turn, these environmental changes may have led to rise in atmospheric oxygen that enabled the explosion of new life forms around 500 million years ago.
Answer:
Avogadro's number is the number of particles in one mole of anything. In this context, it is the number of atoms in one mole of an element. It's easy to find the mass of a single atom using Avogadro's number. Simply divide the relative atomic mass of the element by Avogadro's number to get the answer in grams.
Dalton Found out there was a small, hard indestructible sphere that is the smalles part of an element.He created his own Atomic Theory:
-All Matter is made up of small particles called atoms.
-Atoms cannot be created, destroyed, or divided into smaller particles.
-All atoms of the same element are identical in mass and size. The atoms of one element are different in mass and size from the atoms of other elements.
<span>-Compounds are created when atoms of different elements link together in definite proportions.
</span><span>Rutherford had found the positively charged nucleus in the middle of every atom using his Gold Foil Experiment. While doing this experiment, he expected these particles to just pass right through the foil but they bounced right back. He also proposed there were negatively charged electrons revolving around the nucleus.
</span><span>Thompson found negative electrons and inferred atoms also contain negative particles. He inferred there was a lump of positively charged material, with negative electrons throughout. He used the Raisins Bun Model to explain.
</span>Chadwick <span>proved that it consisted of a neutral particle with about the same mass as a proton "Neutron" is the name given to the particle</span>
Bohr believed Rutherford's prediction was correct, but it wasn't complete. Bohr proposed electrons could only move between energy levels, rather then being able to move everywhere.
Answer:
Mechanical advantage = load/<u>effort</u>
Explanation:
Mechanical advantage is like a ratio of load to effort and many machines like pulleys depend on this relationship between load and effort for it to work.
Answer:
See explanation below
Explanation:
The question is incomplete, however, I found a question very similar to this, and I'm assuming this is the question you are asking to answer. If it's not, please tell me which one it is. Here's a tip for you to get an idea of how to solve.
Picture 1, would be the original question. Picture 2 is the answer of it.
Now, This is a E1 reaction where this type of reactions are taking place in two steps. The first step is the formation of the carbon cation, this step is always slow. The secon step is the addition of a nucleophyle, or, in this case, formation of a pi bond, and we get a alkene.
Hope this can help you
