The untrue statement is that they high melting points.
The covalent compounds are the compounds exhibiting strong intra-molecular bonds. This is due to the tightness of the atoms within the covalent molecules. The force of attraction between the individual molecules in a covalent compound seems to be weak. The covalent compounds exhibit weak intermolecular forces that hold the atoms together due to this they have a low melting point.
Here we have to choose the correct statement on the effect of temperature on the motion of the molecules and atoms of a gas.
As the temperature increases the molecules and atoms move faster.
As per the kinetic theory of gas molecules and atoms the kinetic energy (K.E.) of the atom or molecules is related to temperature by the equation
K.E. =
kT ( k = Boltzmann constant, T = temperature.
Thus as the temperature increases the K.E. increases thus the atom or molecules move faster.
With the decrease of temperature the movement of the atoms or molecules will be less and they will be near to each other.
The increment of temperature increase the K.E. thus the atoms or molecules move apart from each other.
With the decrease of temperature the movement of the atoms or molecules decreases.
There are many examples of chemical equilibrium all around you. One example is a bottle of fizzy cooldrink. In the bottle there is carbon dioxide (CO2) dissolved in the liquid. There is also CO2 gas in the space between the liquid and the cap
Alcohol is a pure substance