One might imagine that the breaking of ionic interactions would require a very high- energy input we have already seen that diamonds do not dissolve in water because actual covalent bonds have to be broken. That would be true if all we considered was the energy required to break the ionic interactions, as indicated by the fact that NaCl melts at oC and boils at oC. But we know that substances like NaCl dissolve readily in water, so clearly there is something else going on.
The trick is to consider the whole system when NaCl dissolves, just like we did for molecular species. We need to consider the interactions that are broken and those that are formed.
The positive ends of water molecules the hydrogens interact with the chloride ions, while the negative end of the water molecules the oxygen interacts with the sodium ions. So the ion on the surface of the solid interacts with water molecules from the solution; these water VisChem animation from molecules form a dynamic cluster around the ion. The process by which solvent molecules interact with and stabilize solute molecules in solution is called solvation.
A chemical compound is made up of many identical molecules formed from atoms from more than one element, attached by chemical bonds. However, not all compounds are created equally. Different things happen to ionic compounds and covalent compounds when they dissolve in water. When ionic compounds dissolve in water they go through a process called dissociation, splitting into the ions that make them up. However, when you place covalent compounds in water, they typically do not dissolve but form a layer on top of the water.
Ionic compounds are molecules consisting of oppositely charged ions, which are ions with both negative and positive charges. Covalent compounds are non-metals bound together, made up of two electrons shared between two atoms.
Ionic compounds have a high melting and boiling point, but covalent compounds have a comparatively lower melting and boiling point.
This is because ionic compounds need a very large amount of energy to break their ionic bonds and separate the positive and negative charges.
Sodium bromide, calcium chloride and magnesium oxide are examples of ionic compounds, while ethanol, ozone, hydrogen and carbon dioxide are examples of covalent compounds.
When ionic compounds dissolve in water, they break apart into the ions that make them up through a process called dissociation. Why is ionic bonding important? What is the ionic compound formula of sodium sulfate? What is the ionic compound formula of ammonium sulfate? What is the ionic compound formula of magnesium nitrate? What is the ionic compound formula of sodium hydroxide?
What is the ionic compound formula of sodium phosphate? How do ionic bonds differ from covalent?
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