Name: ______Key______Date: ______
Study Guide Chapter 13
States of Matter
Know how to convert between the following units of pressure: mm Hg, atm, and kPa.
What is the relationship, at STP, between the three units of pressure listed above?
760 mmHg = 1 atm = 101.3 kPa
Convert 366 mm Hg to atmospheres and kilopascals.
366 mm Hg 760 mm Hg
------= ------
X101.3 kPa
(760mm Hg) (X) = (366 mm Hg) (101.3 kPa)
(366 mm Hg )(101.3 kPa)
X= ------
760 mm Hg
X = 48.8 kPa
Convert 4.75 atm to millimeter of mercury and kilopascals.
4.75 atm 1.00 atm
------= ------
X760 mm Hg
(1atm)(X) = (4.75 atm) (760 mm Hg)
(4.75 atm) (760 mm Hg)
X= ------
1.0 atm
X = 3610 mm Hg or 3.61X103 mm Hg
4.75 atm 1.00 atm
------= ------
X101.3 kPa
(1atm)(X) = (4.75 atm) (101.3 kPa)
(4.75 atm) (101.3 kPa)
X= ------
1.00 atm
X = 481 kPa
Convert 237 kPa to atm and mm Hg.
237 kPa 101.3 kPa
------= ------
X1.00 atm
(101.3 kPa)(X) = (237 kPa) (1.00 atm)
(237 kPa) (1.00 atm)
X= ------
1.00 atm
X = 2.34 atm
237 kPa 101.3 kPa
------= ------
X760 mm Hg
(101.3 kPa)(X) = (237 kPa) (760 mm Hg)
(237 kPa) (760 mm Hg)
X= ------
101.3 kPa
X = 1778 mm Hg or 1.78X103 mm Hg
What is vapor pressure? What tends to happen when there is an increase in the number of particles that vaporize?
A measure of force exerted by a gas above a liquid. As the number of particles that vaporize increases, there is an increase in vapor pressure (Only in a closed system container).
When does a dynamic equilibrium exist between vapor and liquid? Why does it exist?
When the rate of evaporation equals the rate of condensation. This occurs because net amounts of vapor molecules and liquid molecules remain constant, but there is an ongoing exchange of particles.
What is the relationship between temperature and particle energy?
They are directly proportional (i.e. as kinetic energy increases, temperature increases at the same rate).
Why do different liquids have different boiling points?
Some liquids have stronger intermolecular attractions than others. This would cause that liquid to have a higher boiling point.
Think about the following on a particle level.
Why does a liquid start to boil?
When a liquid is heated to a temperature in which particles throughout the liquid vaporize, the liquid begins to boil.
Why does the process of evaporation occur?
The particles on the surface of the liquid have enough kinetic energy to escape into the vapor state (i.e. when light energy changes into thermal energy, particles on the surface will be heated first and begin to evaporate.)
Name at least one physical and chemical property that allows you to distinguish one substance from another and explain why?
Physical property – Melting point – solid ionic compounds tend to have higher melting points than molecular solids because when melting an ionic solid (a salt) each bond between ions needs to be broken. To melt a molecular solid, much weaker intermolecular attractions need to be broken.
Chemical property – Rusting – Some solids, such as iron, rust over time more quickly than other metals. Copper is much more resistant to oxidation.