Answer:
- Fossils are an important part of the study of human evolution When a plant or animal dies its body is acted upon by various forces of nature like wind, air; With time body decomposes and gets covered by layers of soil in millions of years Due to increasing pressure with every layer of soil getting added it creates an impression of the body while it further decays, Even it is acted upon by hot temperature inside So even after millions of years of extinction of a species we can study about it looking at its impression in soil known as Fossil one of the ways is.
Explanation: Hope this helps :)
Answer is c...............
Explanation:
A compound that contains more stronger bonds will need more amount of heat in order to break the bonds so that it changes into vapor state.
In 1-propanol, there is hydrogen bonding and it is stronger in nature. As a result, more amount of heat is required to break the bonds between molecules of 1-propanol.
Whereas in propanone, there will be dipole-dipole interactions which are less stronger than hydrogen bonding. Hence, propanone molecule will need less amount of energy than 1-propanol.
On the other hand, pentane will need more amount of heat as it has longer chain of carbon atoms as compared to methane.
Thus, we can conclude that given compounds are arranged in order of increasing vapor pressure as follows.
methane < pentane < propanone < 1-propanol
- NH₃: Hydrogen bonds;
- CCl₄: London Dispersion Forces; (a.k.a. Induced dipole)
- HCl: Dipole-dipole Interactions.
<h3>Explanation</h3>
Relative strength of intermolecular forces in small molecules:
Hydrogen bonds > Dipole-dipole interactions > London DIspersion Forces.
It takes two conditions for molecules in a substance to form <em>hydrogen bonds</em>.
- They shall contain at least one of the three bonds: H-F, O-H, or N-H.
- They shall contain at least one lone pair of electrons.
NH₃ contains N-H bonds. The central nitrogen atom in an NH₃ molecule has one lone pair of electrons. NH₃ meets both conditions; it is capable of forming hydrogen bonds.
CCl₄ molecules are nonpolar. The molecule has a tetrahedral geometry. Dipole from the polar C-Cl bonds cancel out due to symmetry. The molecule is nonpolar overall. As a result, only London Dispersion Force is possible between CCl₄ molecules.
HCl molecules are polar. The H-Cl bond is fairly polar. The HCl molecule is asymmetric, such that the dipole won't cancel out. The molecule is overall polar. Both dipole-dipole interactions and London Dispersion Force are possible between HCl molecules. However, dipole-dipole interactions are most predominant among the two.
