Which ionic bond is the strongest

When all other parameters are kept constant, doubling the charge of both the cation and anion quadruples the lattice energy. Different interatomic distances produce different lattice energies. The compound Al 2 Se 3 is used in the fabrication of some semiconductor devices. Which has the larger lattice energy, Al 2 O 3 or Al 2 Se 3? The O 2— ion is smaller than the Se 2— ion. Thus, Al 2 O 3 would have a shorter interionic distance than Al 2 Se 3 , and Al 2 O 3 would have the larger lattice energy.

How would the lattice energy of ZnO compare to that of NaCl? ZnO would have the larger lattice energy because the Z values of both the cation and the anion in ZnO are greater, and the interionic distance of ZnO is smaller than that of NaCl. It is not possible to measure lattice energies directly. However, the lattice energy can be calculated using the equation given in the previous section or by using a thermochemical cycle. Figure 1 diagrams the Born-Haber cycle for the formation of solid cesium fluoride.

We begin with the elements in their most common states, Cs s and F 2 g. In the next step, we account for the energy required to break the F—F bond to produce fluorine atoms. Converting one mole of fluorine atoms into fluoride ions is an exothermic process, so this step gives off energy the electron affinity and is shown as decreasing along the y -axis.

We now have one mole of Cs cations and one mole of F anions. These ions combine to produce solid cesium fluoride. The enthalpy change in this step is the negative of the lattice energy, so it is also an exothermic quantity. In this case, the overall change is exothermic.

Table 5 shows this for cesium chloride, CsCl 2. Thus, the lattice energy can be calculated from other values. For cesium chloride, using this data, the lattice energy is:. The Born-Haber cycle may also be used to calculate any one of the other quantities in the equation for lattice energy, provided that the remainder is known.

Lattice energies calculated for ionic compounds are typically much higher than bond dissociation energies measured for covalent bonds. Keep in mind, however, that these are not directly comparable values. For ionic compounds, lattice energies are associated with many interactions, as cations and anions pack together in an extended lattice.

For covalent bonds, the bond dissociation energy is associated with the interaction of just two atoms. The strength of a covalent bond is measured by its bond dissociation energy, that is, the amount of energy required to break that particular bond in a mole of molecules. Multiple bonds are stronger than single bonds between the same atoms. The enthalpy of a reaction can be estimated based on the energy input required to break bonds and the energy released when new bonds are formed.

For ionic bonds, the lattice energy is the energy required to separate one mole of a compound into its gas phase ions. Lattice energy increases for ions with higher charges and shorter distances between ions. Lattice energies are often calculated using the Born-Haber cycle, a thermochemical cycle including all of the energetic steps involved in converting elements into an ionic compound. Account for the difference. Account for this difference. They tend to be stronger than covalent bonds due to the coulombic attraction between ions of opposite charges.

To maximize the attraction between those ions, ionic compounds form crystal lattices of alternating cations and anions. Ionic compounds are usually formed only between atoms whose difference in electronegativity is large. In our description of ionic bonding, we will explore the questions of what determines the bond length and bond strength of an ionic bond. The sodium ions and chloride ions are dissolved, but not combined into a structure until all the water is removed. Most of the rocks and minerals that make up the Earth's crust are composed of positive and negative ions held together by ionic bonding.

An ionic compound is an electrically neutral compound consisting of positive and negative ions. Oppositely charged particles attract each other. This attractive force is often referred to as an electrostatic force. An ionic bond is the electrostatic force that holds ions together in an ionic compound. The strength of the ionic bond is directly dependent upon the quantity of the charges and inversely dependent on the distance between the charged particles.

A larger ion makes a weaker ionic bond because of the greater distance between its electrons and the nucleus of the oppositely charged ion. We will use sodium chloride as an example to demonstrate the nature of the ionic bond and how it forms. As you know, sodium is a metal and loses its one valence electron to become a cation.