Isomers Different compounds that have the

Isomers different compounds that have the same molecular formula... 

Constitutional isomers different compounds that have the same molecular formula, but differ in their connectivity (the sequence in which their atoms are bounded together). 

Isomers Different Compounds that Have the Same Molecular Formula 14... 

ISOMERS DIFFERENT COMPOUNDS THAT HAVE THE SAME MOLECULAR FORMULA... 

In the introduction we noted that both Berzelius and Wohler were fascinated by the fact that two different compounds with different properties ammonium cyanate and urea pos sessed exactly the same molecular formula CH4N2O Berzelius had studied examples of similar phenomena earlier and invented the word isomer to describe different compounds that have the same molecular formula... 

Different compounds that have the same molecular formula are called isomers If they are different because their atoms are connected m a dif ferent order they are called constitutional isomers... 

Compounds like the two C4M [() molecules and the three C3I I 12 molecules, which have the same formula but different structures, are called isomers, from the Greek isos + meros, meaning "made of the same parts." Isomers are compounds that have the same numbers and kinds of atoms but differ in the way the atoms are arranged. Compounds like butane and isobutane, whose atoms are connected differently, are called constitutional isomers. We ll see shortly that other kinds of isomers are also possible, even among compounds whose atoms are connected in the same order. As Table 3.2 shows, the number of possible alkane isomers increases dramatically as the number of carbon atoms increases. 

As noted on several previous occasions, isomers are compounds that have the same chemical formula but different structures. We ve seen several kinds of isomers in the past few chapters, and it s a good idea at this point to see how they relate to one another (f igure 9.14). 

Isomers are compounds that have the same molecular formulas but different structural formulas. Review the writing of the various structural isomers of alkanes. Make sure that each carbon atom has four bonds. 

A) Geometrical isomers are compounds that have the same molecular formula and the same groups bonded to one another but differ in the spatial arrangement of the groups. In the trans form of this compound, the two methyl groups are on opposite sides. 

Positional isomers are compounds that have the same number and kind if atoms but are arranged (or bonded) in a different order They also have different physical and chemical properties. Butane (figure 3.1) can have two different structures, n-bulanc and 2-melhylpropane ... 

One aspect of stereochemistry is stereoisomerism. Isomers, we recall, are different compounds that have the same molecular formula. The particular kind of isomers that are different from each other only in the way the atoms are oriented in space (but are like one another with respect to which atoms are joined to which other atoms) are called stereoisomers. 

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