Answer:
Modern whales evolved by natural selection over long time periods through descent from common ancestors
Explanation:
According to the evolutionary theory proposed by Darwin, natural selection is a biological process by which organisms adapt and change in response to their environment. In this case, ancient whales that were better suited to environmental conditions survived and produced more offspring than non-adapted individuals. In consequence, predominant adaptive traits observed in modern whales were favored by natural selection in the past, while unsuccessful phenotypes progressively disappeared.
Answer:
cuerpo flota o se hunde es su densidad con respecto a la del líquido en que se sumerge. En cambio, una nuez (densidad = 0.5) flotara en ambos líquidos mientras que una piedra (densidad = 2) se hundirá.
Explanation:
:)
The way you calculate the empirical formula is to firstly assume 100g. To find each elements moles you take each elements percentage listed, times it by one mole and divide it by its atomic mass. (ex: moles of K =55.3g x 1 mole/39.1g, therefore there is 1.41432225 moles of Potassium) Once you’ve completed this for every element you list each elements symbol beside it’s number of moles and divide by the smallest number because it can only go into its self once. After you’ve done this, you’ve found your empirical formula, which is the simplest whole number ratio of atoms in a compound. I’ve added an example of a empirical question I completed last semester :)
<h3>1. <u>Answer;</u></h3>
a. the strong nuclear force is much greater than the electric force.
<h3><u>Explanation</u>;</h3>
- <em><u>For an atom to be stable it means it has enough amount of binding energy to hold its nucleus together permanently. </u></em>
- Therefore, <em><u>an unstable atom lacks enough amount of binding energy to hold its nucleus permanently and thus undergoes decay to achieve stability. Unstable atoms are therefore referred to being radioactive.</u></em>
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Small atoms are stable; <u>this is because they have equal number of protons and neutrons and thus the protons and neutrons fill up energy levels while maximizing the strong force binding the nucleus together. </u>
<h3>9.<u> Answer;</u></h3>
b. change into a different element altogether.
Uranium-238 undergoes alpha decay. Therefore, uranium-238 will <em><u>change into a different element altogether</u></em>.
<h3><u>
Explanation;</u></h3>
- Unstable atoms undergo radioactive decay in order to achieve stability of their nucleus.
- <em><u>Uranium-238 is an example of such atom, which may undergo decay to achieve stability.</u></em>
- <em><u>Alpha decay is one of the types of decays,</u></em> others being beta decay and gamma decay. <em><u>In alpha decay the radioactive isotope undergoes decay such that its mass number is decreased by four and its atomic number is decreased by two.</u></em>
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Therefore, <em><u>Uranium-238 undergoes alpha decay to form a different element whose mass number is 234 and atomic number is 90, known as thorium-234. </u></em>
