Answer:
Physical weathering is caused by purely mechanical changes to the rock, while chemical weathering is caused by chemical reactions.
Explanation:
Chemical weathering happens when the chemicals get diluted and dissolved in water and seep and percolate down the rock surfaces.
Physical weathering happens when rocks are fragmented into minor fragments while ensuring no alterations in their chemical makeup. The main causes behind physical weathering include spontaneous fluctuations in temperature like too high or too low heat or cold
Branched chain alkanes
The alkanes don't contain a functional group and so the branches are numbered from the end that gives the lowest set of position numbers for the branches.
Use the above rules to see how the names of the alkanes below are built up.
The structure of 2-methylbutane is a butane molecule (C4H10) but with a methyl group (CH3) replacing a hydrogen on the second carbon atom in the chain. The structure of 3-methylpentane could be drawn as butane with an ethyl group (C2H5) replacing a hydrogen on the second carbon. Note that this is not 2-ethylbutane. The structure of 2,2-dimethylbutane is butane with two methyl groups replacing the two hydrogens on the second carbon.
