Question

Write the formula for each of the following binary compounds of nonmetallic elements. a. carbon disulfide b. water c. dinitrogen trioxide d. dichlorine heptoxide e. carbon dioxide f. ammonia g. xenon tetrafluoride

Short answer

The formulas for the given binary compounds of nonmetallic elements are: a. Carbon disulfide: \(CS_2\) b. Water: \(H_2O\) c. Dinitrogen trioxide: \(N_2O_3\) d. Dichlorine heptoxide: \(Cl_2O_7\) e. Carbon dioxide: \(CO_2\) f. Ammonia: \(NH_3\) g. Xenon tetrafluoride: \(XeF_4\)

Step-by-step solution

Identify the elements involved and their valency

List the nonmetallic elements that make up each binary compound, along with their valency (the number of electrons an atom gains, loses, or shares to achieve a stable electron configuration). a. Carbon disulfide: carbon (C, valency 4), sulfur (S, valency 2) b. Water: hydrogen (H, valency 1), oxygen (O, valency 2) c. Dinitrogen trioxide: nitrogen (N, valency 3), oxygen (O, valency 2) d. Dichlorine heptoxide: chlorine (Cl, valency 7), oxygen (O, valency 2) e. Carbon dioxide: carbon (C, valency 4), oxygen (O, valency 2) f. Ammonia: nitrogen (N, valency 3), hydrogen (H, valency 1) g. Xenon tetrafluoride: xenon (Xe, valency 4), fluorine (F, valency 1)

Determine the ratio of elements in compound

Use the valency of elements to determine the ratio of elements in each compound. The ratio should result in a neutrally charged compound. a. Carbon disulfide: 1 Carbon atom and 2 Sulfur atoms (1:2 ratio) b. Water: 2 Hydrogen atoms and 1 Oxygen atom (2:1 ratio) c. Dinitrogen trioxide: 2 Nitrogen atoms and 3 Oxygen atoms (2:3 ratio) d. Dichlorine heptoxide: 2 Chlorine atoms and 7 Oxygen atoms (2:7 ratio) e. Carbon dioxide: 1 Carbon atom and 2 Oxygen atoms (1:2 ratio) f. Ammonia: 1 Nitrogen atom and 3 Hydrogen atoms (1:3 ratio) g. Xenon tetrafluoride: 1 Xenon atom and 4 Fluorine atoms (1:4 ratio)

Write the formula for each binary compound

Using the ratio of elements determined in the previous step, write the formula for each binary compound. a. Carbon disulfide: CS_2 b. Water: H_2O c. Dinitrogen trioxide: N_2O_3 d. Dichlorine heptoxide: Cl_2O_7 e. Carbon dioxide: CO_2 f. Ammonia: NH_3 g. Xenon tetrafluoride: XeF_4

Key concepts

Valency in Chemical Bonding

Valency is a fundamental concept in chemistry that refers to the ability of an atom to bond with other atoms. It is determined by the number of electrons an atom can lose, gain, or share when it reacts to form a compound. The valency corresponds to the number of hydrogen atoms that can combine with, or displace, one atom of the element to form a compound.

To comprehend valency, consider the electronic configuration of atoms. Elements aim to reach a stable configuration, which often resembles the nearest noble gas. This can be achieved by sharing, losing, or gaining electrons, forming covalent or ionic bonds respectively. For example, in water (H_2O), hydrogen has a valency of 1 and oxygen has a valency of 2. This means that two hydrogen atoms (each sharing one electron) will pair with one oxygen atom (sharing two electrons) to create a stable compound with a complete valence shell.

Exercise Connection

When writing chemical formulas for binary compounds of nonmetals, such as water (H_2O) and carbon dioxide (CO_2), understanding valency is crucial. It allows us to predict how many atoms of each element will be needed to balance the compound. The valency of carbon is 4, so in carbon dioxide, one carbon atom shares four electrons with two oxygen atoms, hence the formula CO_2, which maintains a neutral overall charge.

Writing Chemical Formulas

Writing chemical formulas involves combining symbols and numbers to represent the composition of a substance. The goal is to depict not only the types of atoms present but also their ratios as dictated by their valency. To write a correct chemical formula, follow these steps:

• Determine the valency of each element.
• Apply the cross-over rule if necessary, which involves using the valency numbers to balance the compound.
• Write the symbols for the elements with their corresponding subscripts indicating the number of atoms of each element in the molecule.
• Ensure that the total charge of cations (positively charged) and anions (negatively charged) equals zero for neutral compounds.

Examples from the exercise show the application of these rules. Ammonia (NH_3) consists of nitrogen with a valency of 3 and hydrogen with a valency of 1. Following the steps, we can deduce that for every nitrogen atom, there must be three hydrogen atoms to create a balanced and neutral molecule.

Binary Compounds of Nonmetals

Binary compounds are composed of two different elements. When both elements are nonmetals, they typically form covalent bonds by sharing electrons until both atoms achieve full valence shells. This sharing results in a molecule with a stable configuration. The prefixes in the names of these compounds, such as 'di-' for two or 'tri-' for three, indicate the number of atoms.

For example, consider dinitrogen trioxide (N_2O_3). This indicates a compound consisting of two nitrogen atoms, each with valency 3, and three oxygen atoms, each with valency 2. Utilizing the ratios, we can balance the compound correctly. The infix '-ide' often signifies that we're dealing with a binary compound; for instance, carbohydrates contains carbon (C) and sulfur (S), each bringing its valency 4 and 2 respectively, resulting in the formula CS_2.

Importance of Names and Formulas

Understanding the nomenclature and formulas of binary compounds of nonmetals is vital as it allows precise communication in science. For instance, carbon dioxide (CO_2) and carbon monoxide (CO) are vastly different compounds with distinct properties and safety considerations, despite both being composed of the same elements.