Like pure water is H2O, so why does it liquefy at such a different temperature compared with pure liquid Hydrogen or Liquid Oxygen, the elements it's made of?
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Why are liquid Hydrogen and liquid Oxygen so cold compared to Water, which is made of the two?
Like pure water is H2O, so why does it liquefy at such a different temperature compared with pure liquid Hydrogen or Liquid Oxygen, the elements it's made of?
What properties determine whether a substance is a solid, liquid, or gas at room temperature?
Bonds!
H2, N2, O2, F2, and Cl2 are diatomic molecules, so the bond between the 2 atoms is nonpolar. This means the 2 ends of these molecules have no net charge, so the attraction force between these molecules is very low.
H2O is a polar molecule. The Oxygen atom of one water molecule is attracted toward the 2 Hydrogen atoms of another water molecule.
Nonpolar molecules have a very low force of attraction for each other, so, their collisions are very elastic. This means velocity of the molecules is the same after collision as before collision. At room temperature, this low force attraction is not strong enough to hold the molecules close together, so bond can form between these nonpolar molecules.
As the temperature decreases, the kinetic energy decreases. At temperatures below -222°C, O2 is a liquid. The low force of attraction IS strong enough to hold O2 molecules close together, so bonds will form and O2 gas will become O2 liquid.
At room temperature, the kinetic energy of the molecules of polar molecules, like H2O, is not strong enough to break the polar bonds between H2O molecules, so H2O is a liquid.
When the temperature is below 0° C or above 100°C, water is a solid or a gas, due to the strength of attraction of the polar bonds, the kinetic energy of the molecules, and entropy of H2O when the temperature is below 0° C or above 100°C.
When you study, the Gibb’s Free energy equation, you will learn about the affects of bond energy, temperature, and entropy, on the stability of a substance.
Like pure water is H2O, so why does it liquefy at such a different temperature compared with pure liquid Hydrogen or Liquid Oxygen, the elements it's made of?
What properties determine whether a substance is a solid, liquid, or gas at room temperature?
Bonds!
H2, N2, O2, F2, and Cl2 are diatomic molecules, so the bond between the 2 atoms is nonpolar. This means the 2 ends of these molecules have no net charge, so the attraction force between these molecules is very low.
H2O is a polar molecule. The Oxygen atom of one water molecule is attracted toward the 2 Hydrogen atoms of another water molecule.
Nonpolar molecules have a very low force of attraction for each other, so, their collisions are very elastic. This means velocity of the molecules is the same after collision as before collision. At room temperature, this low force attraction is not strong enough to hold the molecules close together, so bond can form between these nonpolar molecules.
As the temperature decreases, the kinetic energy decreases. At temperatures below -222°C, O2 is a liquid. The low force of attraction IS strong enough to hold O2 molecules close together, so bonds will form and O2 gas will become O2 liquid.
At room temperature, the kinetic energy of the molecules of polar molecules, like H2O, is not strong enough to break the polar bonds between H2O molecules, so H2O is a liquid.
When the temperature is below 0° C or above 100°C, water is a solid or a gas, due to the strength of attraction of the polar bonds, the kinetic energy of the molecules, and entropy of H2O when the temperature is below 0° C or above 100°C.
When you study, the Gibb’s Free energy equation, you will learn about the affects of bond energy, temperature, and entropy, on the stability of a substance.