Video Transcript
The element mercury melts at negative
38.8 degrees Celsius and boils at 356.7 degrees Celsius. What will the state of matter of mercury
be at zero degrees Celsius?
Mercury is a transition metal. It has the chemical symbol Hg. And as a metal, we might expect it to
exist in a lattice of regular atoms fixed in place or in other words as a solid. But the question tells us that mercury
melts at negative 38.8 degrees Celsius. What this means is if we provide enough
energy to our solid mercury, the individual particles in mercury will start to move over one
another. And the whole thing will become a fluid
or a liquid. And the temperature at which this happens
is negative 38.8 degrees Celsius. So, below this temperature, mercury is a
solid. And above this temperature, mercury is a
liquid.
The question also tells us that mercury
boils at 356.7 degrees Celsius. What this means is that when we get to
356.7 degrees Celsius, all the liquid will start getting enough energy to escape the
attractions between one another. And they’ll become a gas. And the temperature at which this occurs
is 356.7 degrees Celsius. So, we have melting, moving from a solid
to a liquid, and boiling, moving from a liquid to a gas. And mercury is liquid below 356.7 degrees
Celsius and a gas above it. All we need to do is figure out what
state of matter mercury will be in at zero degrees Celsius.
Zero degrees Celsius is greater than the
melting point of mercury and it’s less than the boiling point of mercury. Therefore, the state of matter that
mercury will be in at zero degrees Celsius is liquid.