Answer:
<em>Option A. It was delivered by comets that crashed into Earth's surface.</em>
Explanation:
<em><u>Uranium (U) is a chemical element with atomic number 92.</u></em>
<em />
<em>For many years, a large number of scientists have been studying the abundance and origin of the isotopes of uranium in Earth</em>. <u>According to some theories, the Earth's uranium was produced in one or more supernovae</u> (an explosive brightening of a star), in wich, the main process consists in the rapid capture of neutrons by seed nuclei at great rates. <u>Another theory proposes that uranium is created during the merger of two neutron stars</u> (neutron stars are very dense), because, when such dense bodies come closer together the gravitational force cause them to merge, producing huge amounts of hevy metals like uranium.
<u><em>Many analyses have been made of the uranium in rocks of the Earth. These measurements shows that the abundance of uranium is bigger in the crust and upper mantle of the Earth</em></u>.
So, knowing that Earth's uranium was produced through one of these processes, <u><em>the best answer is option A, the uranium was delivered by comets that crashed into Earth's surface.</em></u>
Have a nice day!
Copper. thats the way copper oxidized. like the statue of liberty
Because water is polar and oil is nonpolar, their molecules are not
attracted to each other. The molecules of a polar solvent like water are
attracted to other polar molecules, such as those of sugar. This explains
why sugar has such a high solubility in water. Ionic compounds, such
as sodium chloride, are also highly soluble in water. Because water
molecules are polar, they interact with the sodium and chloride ions.
In general, polar solvents dissolve polar solutes, and nonpolar solvents
dissolve nonpolar solutes. This concept is often expressed as “Like
dissolves like.”
So many substances dissolve in water that it is sometimes called
the universal solvent. Water is considered to be essential for life
because it can carry just about anything the body needs to take in
or needs to get rid of.
Answer:
A. Yes, the substance must be water.
Explanation:
The density of a substance is unique to it. Density is defined the as the amount of substance contained per volume.
One of the ways of identifying a substance is to determine its density. Every matter is known to have their own specific densities. This makes them different from other substances. The density of gold is unique to it and it differs from that of silver.
In fact, water has density of 1.00gcm⁻³. Experimental errors and some little factors must have altered our expected figure. This a case of precision and accuracy in the experiment.
