Hydrogen fluoride has a boiling point of 19 degree Celsius whereas water has a boiling point of 100 degree Celsius...... Explain
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The boiling point of a substance is the temperature at which its vapor pressure equals the atmospheric pressure, allowing the substance to change from a liquid to a gas phase.
The difference in boiling points between hydrogen fluoride (HF) and water (H2O) can be explained by their differing molecular structures and intermolecular forces.
Hydrogen fluoride (HF) is a covalent compound formed by a polar covalent bond between hydrogen and fluorine atoms. The fluorine atom is highly electronegative, causing the bond to be highly polar. This polarity leads to the formation of strong hydrogen bonds between HF molecules. These hydrogen bonds require a certain amount of energy to break, which is why hydrogen fluoride boils at a relatively low temperature of 19 degrees Celsius.
On the other hand, water (H2O) is a polar molecule with two hydrogen atoms covalently bonded to an oxygen atom. Due to the high electronegativity of oxygen, the molecule exhibits a highly polar nature. These polar molecules also form strong hydrogen bonds with each other. The strength of these hydrogen bonds in water is greater than the hydrogen bonding in hydrogen fluoride due to the presence of two hydrogen atoms. As a result, it requires more energy to overcome these hydrogen bonds and boil the water, making its boiling point higher at 100 degrees Celsius.
In summary, the difference in boiling points between hydrogen fluoride and water can be attributed to the differences in their molecular structures, polarity, and strength of intermolecular forces such as hydrogen bonding. These factors determine the amount of energy required to change the substance from a liquid to a gas phase.