Question

(a) Is the compound \(\mathrm{CBr}_{3} \mathrm{CH}=\mathrm{CHCH}_{3}\) saturated or unsaturated? Explain. (b) What is wrong with the formula \(\mathrm{CH}_{2}=\mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{3} ?\)

Short answer

(a) The compound \(CBr_{3}CH=CHCH_{3}\) is unsaturated because it contains a carbon-carbon double bond. (b) The formula \(CH_{2}=CH_{2}CH_{2}CH_{3}\) is incorrect because the second carbon atom has more than the allowable number of bonds (5 instead of 4).

Step-by-step solution

First, look at the given chemical formula for the compound: CBr3CH=CHCH3. We will identify the types of bonds present in the compound and determine if it contains any double or triple bonds. #Step 2: Identifying the bond types in CBr3CH=CHCH3#

In the compound's formula, we can see a double bond between two carbon atoms, represented by "CH=CH." The presence of this double bond indicates that the compound is unsaturated. #Step 3: Conclusion about CBr3CH=CHCH3 compound#

The compound CBr3CH=CHCH3 is an unsaturated compound because it contains a carbon-carbon double bond. #Step 4: Analyzing the formula CH2=CH2CH2CH3#

Now, we will analyze the given chemical formula CH2=CH2CH2CH3. In particular, we will examine the bonds between the carbon atoms and identify any issues with the formula. #Step 5: Identifying the bond issue in CH2=CH2CH2CH3#

When we examine the bonds in CH2=CH2CH2CH3, we can see that there is a double bond between the first two carbon atoms, represented by "CH2=CH2." However, the rest of the formula shows single bonds between the remaining carbon atoms. This means that the second carbon atom is forming an additional bond beyond its maximum capacity. Carbon can form a maximum of 4 bonds, but in this formula, the second carbon atom is forming 5 bonds (double bond with the first carbon atom, single bond with the third carbon atom, and two hydrogen atoms). This is not possible according to the valence rules for carbon. #Step 6: Conclusion about the formula CH2=CH2CH2CH3#

The formula CH2=CH2CH2CH3 is incorrect because the second carbon atom, with its existing double bond, has more than the allowable number of bonds. It should either have a single bond with the first carbon atom or form one less bond in some other way.

Key concepts

Chemical Bonding

Chemical bonding is the process where atoms connect to each other to create compounds. There are two main types of chemical bonds: covalent bonds and ionic bonds. For the exercise given in the original problem, we're particularly interested in covalent bonds, where atoms share electrons to achieve stability.

In the compound \( \mathrm{CBr}_{3} \mathrm{CH}=\mathrm{CHCH}_{3} \), we see an example of a double covalent bond between two carbon atoms. When two carbon atoms share two pairs of electrons, a double bond is formed, indicated by the "=" in the formula. This type of bonding affects the properties of the compound, such as letting it react more easily with other substances.

In contrast, single bonds occur when atoms share just one pair of electrons. This is usually less reactive. Recognizing the type of bond in a compound is crucial for predicting its chemical behavior, which is why identifying double bonds helps us determine if a compound is saturated or unsaturated.

Valency Rules

Valency refers to the ability of an atom to bond with others, determined by the number of electrons available for bonding in its outermost shell. For carbon, the valency is four, meaning it can form up to four bonds. This is crucial in organic chemistry and is the core of understanding the error in \( \mathrm{CH}_2=\mathrm{CH}_2 \mathrm{CH}_2 \mathrm{CH}_3 \).

Let's break down the formula: In \( \mathrm{CH}_2=\mathrm{CH}_2 \), two carbon atoms are connected by a double bond. Each carbon both satisfies a portion of its valency with this shared pair of electrons. Thus, both can form additional two bonds to complete its configuraion. The third carbon participating in the error attempts to make five connections: two to hydrogen, one to each of two adjacent carbons, and an additional bond, which violates carbon's normal bond capacity.

Understanding these rules assists in validating if molecular structures are feasible. Incorrect valencies result in unstable, non-existent compounds in nature.

Molecular Formulas

Molecular formulas convey the type and number of atoms in a chemical compound. It’s essential to interpret these formulas correctly to understand the structure and behavior of a compound.

In \( \mathrm{CBr}_{3} \mathrm{CH}=\mathrm{CHCH}_{3} \), the formula tells us there are three bromine atoms attached to a carbon, a structural fact helping determine unsaturation due to the double bond. The formula \( \mathrm{CBr}_{3} \mathrm{CH}=\mathrm{CHCH}_{3} \) is very telling about specific configurational aspects, giving insight into potential reactions such as additions.

Conversely, \( \mathrm{CH}_2=\mathrm{CH}_2 \mathrm{CH}_2 \mathrm{CH}_3 \) attempts to indicate a similar arrangement, but a misstep in assigning bonds leads to a non-viable formula. Correct interpretation regarding multiple bonding nature and valency constraints must align to establish chemical structures effectively within molecular formulas. Proper representation ensures accurate communication of chemical innovation and functionality.