Chapter 3 Flashcards
A Solid is …..
State of matter that has a definite shape and a definite volume (never change) i.e. pencil, book, quarter
3 States of Matter
Solid, Liquid, Gas
Liquid is a ….
State of matter that has a definite volume (never changing), but the shape can change. It’s shape changes with the container. i.e. milk, juice, water
Gas is a ……
State of matter that DOES NOT have a definite volume or shape. It takes on the shape and volume of its container. i.e. air, helium
Kinetic Energy
The energy an object has due to motion. (The faster an object moves the greater its kinetic energy)
Kinetic “Theory”
All particles of matter are in constant motion
Pressure
The result of a force distributed over an area.
The standard unit of measurement for pressure
the pascal (Pa), short for newtons per m2
Formula for pressure
P = force in newtons / area in square meters
What factors affect gas pressure?
- “Raising Temperature” increases pressure
- “Reducing Volume” increase pressure
- “Increasing the Number of particles” will increase pressure
What is “absolute zero”?
The temperature of a gas with a volume of zero Liters also known as 0 Kelvin or -273.15 Celsius
What is “Charles Law”?
The Volume of a gas is directly proportional to its temperature, if the pressure and number of particles remain the same
i.e. v1/t1 = v2/t2 or 1L/3Kelvins = 2L/6Kelvins
What is “Boyles Law”?
States that the volume of a gas is inversely proportional to its pressure if the temperature and number of particles remain constant.
p1v2 = p2v1 or if p=1 v =2 then p=2 v=1
What is a “phase change”?
The reversible physical change that occurs when matter changes from one state of matter to another.
i.e. freezing, melting,vaporization
Six common “phase changes”?
- Melting 2. Freezing 3. Vaporization 4. Condensation 5. Sublimation 6. Deposition
Does the temperature change during “phase change”?
No…. when matter reaches its phase change the temperature stays the same.
i.e. When water reaches its melting point temperature it stays there until it finishes melting.
Is energy absorbed or released during “phase change”?
Yes
What happens to energy during and “Endothermic” Change?
The system absorbs energy
What happens to energy during an “Exothermic” change?
The system releases energy to its surroundings.
What is “vaporization”?
Changing from a liquid to a gas (endothermic change)
What is “Evaporation”?
The process that changes a substance from a liquid to a gas at temperatures below the substances boiling point.
What is “Condensation”?
The phase change when a vapor or gas changes to a liquid. (Endothermic) i.e. morning dew
What is “Sublimation”?
The phase change when a substance changes from a solid to gas or vapor without changing to a liquid first
What is “deposition”?
When a gas or vapor changes to a solid without changing to a liquid first.
Which state of matter has a definite volume but a changing shape?
a. solid b. liquid c. gas d. vapor
b. liquid
In which state(s) of matter can materials take the shape of their containers?
a. solid & liquid b. solid & gas c. liquid & gas d. liquid only
c. liquid & gas
Which statement is true about the atoms in helium gas?
a. they travel in circular paths
b. they have strong attractions to one another
c. they are not closely packed
d. they are arranged in an orderly pattern.
c. they are not closely packed
** the atoms are spread out
If the speed of an object increases, its kinetic energy?
a. decreases b. increases c. stays the same
d. is unpredictable
b. increases
The SI Unit of pressure is the
a. pascal b. newton c. square meter d. psi
a. pascal
Increasing which variable would decrease the pressure of a contained gas?
a. temperature b. # of particles c. boiling pt. d. volume
d. volume
Boyle’s Law relates pressure and
a. temperature b. # of particles c. volume d. mass
c. volume
Which is the following changes is “exothermic”?
a. evaporation b. freezing c. boiling d. sublimation
b. freezing
The phase change that is the reverse of vaporization?
a. freezing b. melting c. condensation d. evaporation
c. condensation
Which of these phase changes does NOT involve changing a liquid into a gas?
a. sublimation b. vaporization c. evaporation d. boiling
a. sublimation
