Question

An organic compound on heating with CuO produces \(\mathrm{CO}_{2}\) but not water. It may be: (a) \(\mathrm{CH}_{4}\) (b) \(\mathrm{CCl}_{4}\) (c) \(\mathrm{CHCl}_{3}\) (d) \(\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{I}\)

Short answer

(b) \( \mathrm{CCl}_4 \).

Step-by-step solution

Analyzing the Problem

We need to identify an organic compound from the given options that produces carbon dioxide (\( \mathrm{CO}_2 \)) but not water upon heating with copper (II) oxide (\( \mathrm{CuO} \)). This implies the compound should not contain any hydrogen atoms, as hydrogen would react to form water (\( \mathrm{H}_2\mathrm{O} \)).

Checking Each Option

We need to analyze each given compound: (a) \( \mathrm{CH}_4 \) contains hydrogen and will produce water.(b) \( \mathrm{CCl}_4 \) contains no hydrogen, thus it cannot form water.(c) \( \mathrm{CHCl}_3 \) contains hydrogen and will produce water.(d) \( \mathrm{C}_2 \mathrm{H}_{5} \mathrm{I} \) contains hydrogen and will produce water.

Identifying the Correct Compound

The compound that does not contain hydrogen and will only produce \( \mathrm{CO}_2 \) without forming \( \mathrm{H}_2\mathrm{O} \) is \( \mathrm{CCl}_4 \) from option (b). Thus, \( \mathrm{CCl}_4 \) is the compound that fits the given condition.

Key concepts

Organic Compounds

Organic compounds are fascinating substances characterized mainly by the presence of carbon atoms, usually bonded to hydrogen. However, they can also include other elements such as oxygen, nitrogen, sulfur, and halogens like chlorine, bromine, or iodine. The versatility of carbon makes it the backbone of organic chemistry, allowing for diverse molecules with varying structures and properties.

Some key properties of organic compounds include:

• They commonly form covalent bonds.
• They often have low melting and boiling points.
• They can be flammable and reactive with substances.

The presence or absence of specific atoms like hydrogen can significantly influence the behavior of these compounds during chemical reactions. For instance, the compound represented by \(\)\( \( \mathrm{CCl}_4\)\) is organic as it contains carbon but notably lacks hydrogen, which impacts its reactivity when involved in reactions such as oxidation.

Chemical Reactions

Chemical reactions are processes in which substances, known as reactants, are transformed into different substances, called products. These reactions are often at the heart of understanding how organic compounds behave and interact under different conditions.

The reaction of organic compounds with copper(II) oxide (\( \mathrm{CuO} \)) as shown in the original exercise is a great example. Here, the focus is on identifying which members of the given options release specific products, such as carbon dioxide. Understanding what elements the compound includes helps predict the products formed during the reaction.

Some notable features of the reactions include:

• Reactions can involve decomposition or synthesis.
• The presence of specific atoms determines the outcome; hydrogen reacts to form water.
• Reactions often involve energy changes, usually in the form of heat or light.

Recognizing the chemical composition of compounds and anticipating their behavior during these reactions can help identify compounds like \( \mathrm{CCl}_4 \) that do not produce water, only \( \mathrm{CO}_2 \), making them unique in their reaction pathway.

Hydrocarbons

Hydrocarbons play a vital role in organic chemistry as they primarily consist of carbon and hydrogen. These compounds form the basis of many organic substances, serving as critical components in fuels and raw materials for chemical synthesis. Despite their general versatility, the absence of hydrogen in a molecule such as \( \mathrm{CCl}_4 \) means it's not classified as a hydrocarbon.

Commonly, hydrocarbons are divided into several types:

• Alkanes are saturated hydrocarbons with single bonds, like methane (\( \mathrm{CH}_4 \)). They readily react to form carbon dioxide and water.
• Alkenes and alkynes are unsaturated, containing double or triple bonds, making them more reactive than alkanes.
• Aromatic hydrocarbons have a stable ring structure, such as benzene.

Each type has distinct properties based on its molecular structure, impacting its reactivity and applications. The absence of hydrogen in compounds like \( \mathrm{CCl}_4 \) distinguishes them from traditional hydrocarbons and defines their unique pathway during chemical reactions.