What new evidence led scientists to change their minds about the geocentric model?

1 answer:

3 0

Galileo disproved the Ptolemaic theory, sanctioned for centuries by the Church, which held the Earth to be the central and principal object in the universe, about which all celestial objects orbited.

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Balance this chemical equation. A coefficient of "1" is understood. Choose option "blank" for the correct answer if the coeffici

larisa86 [58]

The first one have a nice day and good luck

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3 years ago

Bromo-4-fluorohexane has two chiral carbon atoms; therefore, the maximum number of possible stereoisomers that can be formed is

Zepler [3.9K]

Here we have to draw the four isomers of the compound 3-bromo-4-fluorohexane.

The four isomers of the compound is shown in the figure.

In an organic molecule the chiral -C center is that where four (4) different groups are present. In 3-bromo-4-fluorohexane the 3 and 4 positions are chiral centers. The possible isomers of a molecule can be obtained from the formula 2n. As here 2 chiral centers are present thus number of stereoisomers will be 2×2 = 4.

The four different isomers as shown in the figure are 3R-, 4R-; 3S-, 4S; 3R, 4S and 3S-, 4R- 3-bromo-4-fluorohexane.

In the 3-bromo-4-fluorohexane the functional groups are -Br, C₂H₅, -C₃H₆F and -H for 3-position and -F, -C₂H₅, -C₃H₆ and -H for 4-position respectively.

The priority of the -3 position will be Br > C₃H₆F > C₂H₅ > H and for -4 position F > C₃H₆Br > C₂H₅ > H. If the rotation from the higher priority group to lower is clockwise and anticlockwise then the S- and R- notation are used respectively. However if the -H atom is present at the horizontal position then the notation will be reverse.

Thus the four isomers of the compound is shown.