Science 3.3 & 3.4
Why is the volume of a gas the same as the volume of its container?
Because gas particles move and fill the space available,
What did Boyle discover in his experiments on air pumps?
Boyle found that 1. when the pressure of a gas at constant temperature is increased, the volume of the gas decreases. 2. When the pressure is decreased, the volume increases
What is the purpose of a graph?
Graphs are a way to tell a story with data.
What was Jacque Charles interested in measuring?
He measured the volume of a gas at various temperatures in a container that could change volume.
Who was Robert Boyle?
He was a scientist in the 1600s who wanted to improve air pumps.
Explain how a hot air balloon driver makes his balloon rise.
Heating causes the air inside the balloon to expand. Some of the warm air leaves through the bottom opening of the balloon, keeping the pressure constant. But now, the air inside is less dense than the air outside the balloon, so the balloon begins to rise.
What would happen if a high altitude balloon were fully filled with gas at take-off?
If the balloon were fully filled at takeoff, it would burst before it got very high.
When the temperature is decreased, what happens to the pressure of the gas?
It decreases.
When the temperature of a gas at constant volume is increased, what happens to the the pressure of the gas?.
It increases.
What does a changeable volume allow the pressure to do?
It remains constant.
What was Jacque Charles interested in?
Jacques Charles examined the relationship between the temperature and volume of a gas that is kept at a constant pressure.
Explain how a hot air balloon driver makes his balloon go downward.
The pilot would allow the air in the balloon to cool. The air in the balloon contracts, and more air enters through the opening. The density of the air inside increases, and the balloon starts downward.
What is pressure?
The pressure of the gas is the force of its outward push divided by the area of the walls of the container.
What does the vertical axis, or y-axis show?
The vertical axis, or y-axis, shows the responding variable.
When it appears on a graph as if the line would continue downward if data could be collected for lower temperatures and the line would pass through the point (0, 0), it is called _____________________
the origin.
Notice that the curve slopes downward from left to right. Also notice that the curve is steep at lower volumes and becomes less steep as volume increases. When a graph of two variables forms this kind of curve, the variables are said ________________________.
to vary inversely with one another.
A graph for Boyle's law shows that the pressure of a gas __________ with its volume at constant temperature.
varies inversely
What are the 3 things you measure when working with a gas?
volume, temperature, and pressure
The graph of Charles's law shows that the volume of a gas is directly proportional to its _______________
kelvin temperature under constant pressure.
What does a graph tell you?
A graph is a diagram that tells how two variables, or factors that change, are related.
In the pressure-volume experiment, the manipulated variable is the _____________
A. pressure. B. volume. C. temperature. D. kinetic energy.
According to Boyle's law, when the pressure of a gas increases its volume --------
A. stays the same. B. increases. C. decreases. D. always doubles.
According to Charles's law, when the temperature of a gas increases its volume ------
A. stays the same. B. increases. C. decreases. D. always doubles.
A helium balloon bursts as it rises in the atmosphere because the ---
A. temperature increases so the volume of helium expands. B. temperature decreases so the volume of helium expands. C. air pressure increases so the volume of helium expands. D. air pressure decreases so the volume of helium expands.
A measure of the average kinetic energy of the particles of a substance is its
A. temperature. B. pressure. C. force. D. volume.
Why do truck tires sometimes burst on hot days?
As the temperature increases, so does the pressure of the air inside the tire. If the pressure becomes greater than the tire can hold, the tire will burst.
How does Boyle's law apply to a bicycle pump?
As you push on the plunger, the volume of air inside the pump cylinder gets smaller and the pressure increases, forcing air into the tire.
What is Charles' law?
Charles found that 1. when the temperature of a gas is increased at constant pressure, its volume increases. 2. When the temperature of a gas is decreased at constant pressure, its volume decreases.
What is concentration?
Concentration is the number of particles in a given unit of volume.
When does constant volume occur?
Constant volume means that the gas is in a closed, rigid container.
What are the 3 things you label in a graph?
Each axis is labeled with 1. the name of the variable, 2. the unit of measurement, and 3. a range of values.
What is the unit of measure for pressure?
Pressure is measured in units of pascals (Pa) or kilopascals (kPa). (1 kPa = 1,000 Pa.)
How is Boyle's law used in high altitude balloons?
Researchers fill the balloons with only a small fraction of the helium gas that the balloons can hold. As a balloon rises through the atmosphere, the air pressure around it decreases and the balloon expands.
What does it mean when the variables vary inversely from one another?
Such a relationship means that when one variable goes up, the other variable goes down in a regular way.
What is temperature?
Temperature is a measure of the average energy of random motion of the particles of a substance.
When does temperature go up?
The faster the particles are moving, the greater their energy and the higher the temperature.
What makes a gas-filled object firm?
The firmness of a gas-filled object comes from the pressure of the gas.
What does the horizontal axis, or x-axis show?
The horizontal axis, or x-axis, shows the manipulated variable.
What is Boyle's law?
This relationship between the pressure and the volume of a gas is called Boyle's law: 1. when the pressure of a gas at constant temperature is increased, the volume of the gas decreases. 2. When the pressure is decreased, the volume increases.
True or false: The faster gas particles are moving, the greater their energy and the lower the temperature.
True or False?
What units of measurement are used to measure volume?
Volume is measured in cubic centimeters (cm3), milliliters (mL), liters (L), and other units.
What is volume?
Volume is the amount of space that matter fills.
The force pushing on a surface divided by the area of that surface is called ________________________.
_____________________
What is the formula used to calculate pressure? __________________________________
_______________________
The volume of a gas is the same as the volume of its ________________________.
__________________________
What does Boyle's law say about the relationship between the pressure and volume of a gas?
__________________________
When a graph of two variables forms a curve that slopes downward from left to right, the variables are said to ________________ with one another.
__________________________
Why does a ball leak air even when it has a tiny hole?
__________________________
Suppose a gas is kept in a closed, rigid container. If the temperature of the gas is increased, what happens to its pressure on the container?
____________________________
What does the graph for Boyle's law show about the relationship between the pressure and volume of a gas?
_____________________________
If the temperature of a gas is decreased at constant pressure, what happens to its volume?
_______________________________
If the temperature of that gas in the container is decreased, what happens to its pressure?
________________________________
Why does a hot air balloon rise when the air inside it is heated?
________________________________
What can cause tires to burst on long trips in warm weather?
_________________________________
if a gas is cooled enough, it will condense into a _______________
a liquid.
____ temperature ____ Charles's Law ____ pressure ____ Boyle's Law
a. explains the relationship between the pressure and volume of gas at a constant temperature b. explains the relationship between the temperature and volume of gas kept at a constant pressure c. a measure of the average energy of motion of the particles of a substance d. a measure of the force of the outward push caused by the movement of particles of a gas
When a graph of two variables is a straight line passing through the origin, the variables are said to be ___________________________
directly proportional to each other.
What is the formula? Pressure =
force ---- area
