Problem 90
Question
The number and type of bonds between two carbon atoms in \(\mathrm{CaC}_{2}\) are (a) one sigma and one \(\pi\) bond (b) one sigma and two \(\pi\) bonds (c) one sigma and one and a half \(\pi\) bonds (d) one sigma bond
Step-by-Step Solution
Verified Answer
(b) One sigma and two \(\pi\) bonds.
1Step 1: Understand the Structure of Calcium Carbide
Calcium carbide (\(\mathrm{CaC}_2\)) is an ionic compound consisting of calcium ions (Ca\(^{2+}\)) and acetylide ions (C\(_2^{2-}\)). The structure of the acetylide ion is key to answering this question.
2Step 2: Examine the Acetylide Ion
The acetylide ion, C\(_2^{2-}\), consists of two carbon atoms triple-bonded together. In a triple bond, there is one sigma (\(\sigma\)) bond and two pi (\(\pi\)) bonds between the carbon atoms.
3Step 3: Determine the Bonding Configuration
Since the acetylide ion has a triple bond between the two carbon atoms, the bonding consists of one \(\sigma\) bond and two \(\pi\) bonds, aligning with the definition of a carbon-carbon triple bond.
Key Concepts
Acetylide IonCarbon-Carbon Triple BondIonic Compound
Acetylide Ion
In the world of chemistry, understanding ions is fundamental. One such important ion is the acetylide ion, which is denoted as C\(_2^{2-}\). This ion is a negatively charged species composed of two carbon atoms. The acetylide ion is a key player in the structure of calcium carbide (CaC\(_2\)). The arrangement of these atoms gives rise to unique chemical properties.
What makes the acetylide ions fascinating is their bonding. Acetylide ions feature a carbon-carbon triple bond, which is a rare and highly stable configuration. This means that within the ion, there are three bonds: one sigma bond and two pi bonds. The presence of the triple bond offers the ion a high degree of reactivity, making it useful in various chemical reactions. It's often employed as a starting material in organic synthesis and plays a critical role in forming new carbon-carbon bonds.
What makes the acetylide ions fascinating is their bonding. Acetylide ions feature a carbon-carbon triple bond, which is a rare and highly stable configuration. This means that within the ion, there are three bonds: one sigma bond and two pi bonds. The presence of the triple bond offers the ion a high degree of reactivity, making it useful in various chemical reactions. It's often employed as a starting material in organic synthesis and plays a critical role in forming new carbon-carbon bonds.
Carbon-Carbon Triple Bond
A carbon-carbon triple bond is a special type of chemical bond where two carbon atoms are joined together by three covalent bonds. This includes one sigma (\(\sigma\)) bond and two pi (\(\pi\)) bonds. The sigma bond is the strongest and results from the head-on overlap of atomic orbitals. Meanwhile, the pi bonds are weaker and result from the side-to-side overlap of parallel p orbitals.
The triple bond engenders stability, and due to its linear nature, it also results in a particular geometry. The angle around the carbon atom in a triple bond is approximately 180 degrees, which is why such bonds in molecules are often depicted as straight lines.
This type of bond is not only strong but also short, providing both stability and rigidity to the molecule. You'll find carbon-carbon triple bonds in various compounds, but they prominently feature in alkynes such as ethyne. They are crucial for the synthesis of complex organic molecules and demonstrate the versatile bonding nature of carbon.
The triple bond engenders stability, and due to its linear nature, it also results in a particular geometry. The angle around the carbon atom in a triple bond is approximately 180 degrees, which is why such bonds in molecules are often depicted as straight lines.
This type of bond is not only strong but also short, providing both stability and rigidity to the molecule. You'll find carbon-carbon triple bonds in various compounds, but they prominently feature in alkynes such as ethyne. They are crucial for the synthesis of complex organic molecules and demonstrate the versatile bonding nature of carbon.
Ionic Compound
An ionic compound consists of positively and negatively charged ions held together by electrostatic forces. In the case of calcium carbide (\(\mathrm{CaC}_2\)), the ionic compound contains calcium ions (Ca\(^{2+}\)) and acetylide ions (C\(_2^{2-}\)). Each part plays a specific role in the compound's overall stability and properties.
The formation of ionic compounds occurs when electrons are transferred from one atom to another, leading to the establishment of ions. Typically, metals like calcium lose their electrons, becoming positively charged, while nonmetals such as the carbon atoms in C\(_2\) gain electrons, becoming negatively charged.
This electron transfer results in a robust attraction, known as ionic bonding, which is responsible for holding the structure of the compound together. Ionic compounds are known for their high melting and boiling points, being electrical conductors in molten or dissolved states, and often forming crystalline solids. Understanding ionic compounds like calcium carbide can demonstrate how different elements combine to form materials with distinct and beneficial properties.
The formation of ionic compounds occurs when electrons are transferred from one atom to another, leading to the establishment of ions. Typically, metals like calcium lose their electrons, becoming positively charged, while nonmetals such as the carbon atoms in C\(_2\) gain electrons, becoming negatively charged.
This electron transfer results in a robust attraction, known as ionic bonding, which is responsible for holding the structure of the compound together. Ionic compounds are known for their high melting and boiling points, being electrical conductors in molten or dissolved states, and often forming crystalline solids. Understanding ionic compounds like calcium carbide can demonstrate how different elements combine to form materials with distinct and beneficial properties.
Other exercises in this chapter
Problem 88
The number of optical isomers formed by hydrogenation of the compound, \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{C}=\mathrm{CHCH}_{3}\) are (a) 0 (b) 1 (c) 2 (
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Which of the following can exhibit optical isomerism? (1) CC[N+](C)(C)C (2) ClC=C=C=CCl (3) CC1CC1 (4) (a) 1 and 2 (b) 2 and 4 (c) 3 only (d) 2 only
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Which of the following has the least hindered rotation about carbon-carbon bond? (a) ethane (b) ethylene (c) acetylene (d) hexachloroethane
View solution Problem 93
The \(\mathrm{Cl}-\mathrm{C}-\mathrm{Cl}\) angle in \(1,1,2,2\)-tetrachloroethene and tetrachloromethane will be about (a) \(120^{\circ}\) and \(109.5^{\circ}\)
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