Sante Barley by Coach Rosalie

Measurable Properties of Gases

In dealing with Gas Laws, it is important to know the commonly used units in volume, pressure and temperature. Please do the activity below to be familiar with the common units used in dealing with Gas Laws.

Gases are generally described based on their measurable properties.

The following measurable properties are usually used in dealing with gas laws:

1. Pressure - the force exerted by the gas on the walls of its container divided by the surface area of the container.
The common units of pressure are the following:
 Pascal (Pa) - standard unit of pressure under Systemé International (SI) which is equivalent to a force of one newton (1N -1 kg m/s2) acting on an area of one square meter.
- Atmosphere (atm)
-Torr
-Millimeter mercury (mm Hg)

Pressure can be converted from unit to another using the following conversion: 1 atm = 760 torr = 760 mm Hg
1 torr = 1 mm Hg
1 atm = 101,325 Pa
2. Volume –defined as the space occupied. The volume of the gas is equal to the volume of the vessel or container.
Common Units of Volume: cubic meter (m3), cubic centimeter (cm3), liter (L)
milliliter (mL)

Pressure can be converted from unit to another using the following conversion: 1 atm = 760 torr = 760 mm Hg
1 torr = 1 mm Hg
1 atm = 101,325 Pa

2. Volume –defined as the space occupied. The volume of the gas is equal to the volume of the vessel or container.
Common Units of Volume: cubic meter (m3), cubic centimeter (cm3), liter (L)
milliliter (mL)

3. Temperature –defined as the degree of hotness or coldness. Units: degree Celsius (oC), degree Fahrenheit (oF), Kelvin (K)
The temperature of a gas together with its atmospheric pressure differ from place to place and from time to time. As the volume of a gas is dependent on its temperature and pressure, it is significant to have a set of standard conditions for these quantities. This set of standard condition is named as standard temperature and pressure or simply STP.

The standard temperature is 0 ⁰C or 273.15 K and the standard pressure is 1 atm pressure. This is the freezing point of pure water at sea level atmospheric pressure. At STP, one mole of gas occupies 22.4 L of volume.

Boyle's Law Quiz
Part I: True or False (15 items)
Write TRUE if the statement is correct and FALSE if it is incorrect.
1. Robert Boyle was a French scientist who studied the relationship between pressure and volume.
2. In Boyle's Law, temperature must remain constant.
3. The standard unit of pressure in SI is Pascal (Pa).
4. As pressure increases, the volume of a gas also increases at constant temperature.
5. One atmosphere is equal to 760 mm Hg.
6. Gas particles have strong intermolecular forces of attraction.
7. The volume of a gas is inversely proportional to its pressure at constant temperature.
8. In Boyle's Law equation, P₁V₁ = P₂V₂, the units of pressure and volume must be consistent.
9. At STP, one mole of gas occupies 22.4 L of volume.
10. When a balloon is pressed, the pressure inside decreases.
11. Pascal is equivalent to a force of one newton acting on an area of one square meter.
12. The value of k in Boyle's Law (PV = k) depends on the mass of gas and temperature.
13. Gas molecules are located close together because of strong attractions.
14. 1 atm is equal to 101,325 Pa.
15. When filling a tire with air, you are decreasing the volume and increasing the pressure.

Part II: Identification (10 items)
Identify what is being described in each statement.
1. The English scientist who studied the relationship between volume and pressure in 1662.
2. The gas law that states volume is inversely proportional to pressure at constant temperature.
3. The SI standard unit of pressure.
4. The force exerted by gas on the walls of its container divided by the surface area.
5. The standard temperature in Kelvin at STP.
6. The amount of space occupied by a gas.
7. The pressure equivalent to 760 torr.
8. The mathematical equation representing Boyle's Law when comparing two conditions.
9. The term for the set of standard conditions (0°C and 1 atm) used in gas measurements.
10. The constant value obtained when pressure is multiplied by volume in Boyle's Law.

Physical Science
Quarter 4 – Module 1
Earth in the Universe

WHAT I KNOW

Multiple Choice. Read the statements below. Choose and write the letter of the correct answer in a separate sheet.
1. Who discovered the laws of planetary motion?
A. Copernicus
B. Galileo
C. Kepler
D. Newton

2. What is referred as the motion of the earth around the sun?
A. revolution
B. rotation
C. season
D. orbit

3. Who gave a true explanation that earth is spherical based on stars position and constellations?
A. Aristotle
B. Eratosthenes
C. Ptolemy
D. Seleucus

4. Who used the round earth theory and shadows to measure the circumference of the earth?
A. Bede
C. Eratosthenes
B. Plato
D. Alexander the Great

5. Which spiral shape galaxy the Earth belongs?
A. comet
B. cartwheel
C. black eye
D. milky way

6. Who calculated the length of the year as 365 and 6 hours.
A. Aristarchus
B. Copernicus
C. Eudoxus
D. Ptolemy

7. Which of the following is NOT TRUE about uniform circular motion and epicycles which were catalogued by Ptolemy in 150 A.D.?
A. The sun is the center of the universe.
B. The earth is the center of the universe.
C. Heavenly bodies move in circular motion.
D. The objects in the heavens are made from perfect material and cannot change their intrinsic properties.

8. Which of the following is NOT included in the Kepler’s law of planetary motion?
A. equal area
B. law of periods
C. elliptical orbit
D. laws of motion

9. Who postulated the heliocentric theory?
A. Copernicus
B. Heraclitus
C. Ptolemy
D. Pythagoras

10. Which of the following devices is used to study “the heavens” systematically?
A. gramophone
B. microscope
C. telephone
D. telescope

11. Who proposed that the Earth is not only round, but it also revolves around the sun?
A. Aristotle
B. Eratosthenes
C. Ptolemy
D. Seleucus

12. Who created a map which shows Earth as being round?
A. Aristotle
B. Eratosthenes
C. Ptolemy
D. Seleucus

13. Which is used as the basis for ancient calendars?
A. tides
B. eclipse
C. phases of the moon
D. alignment of the moon and sun

14. Which is/are other names of the North Star?
A. Polaris C. Ursa Minor
B. Alpha Umi
C. Ursa Minor
D. All of the above

15. Who proposed the sun-centered theory?
A. Brahe ]
B. Copernicus
C. Kepler
D. Ptolemy

Earth is Sphere According to Greeks

Earth was thought to be anything but a sphere by ancient people. Mesopotamians and Egyptians saw the Earth was flat, as did the early Greeks. Greeks proposed theories and proved that the earth was round.

Greek philosophers in the early times thought about the concept of earth which is round but failed to give explanation about it, like what Plato believed and shared to the people of Athens but showed no explanation, not until his great student Aristotle was able to show proof that the earth is round.

WHAT'S NEW

Without using a telescope, try locating the planets Mercury, Venus, Mars, Jupiter, and Saturn in the night sky. Do this tonight and let us figure out which of the heavenly bodies were you able to see. But, how to locate Venus and Jupiter?

For those who do not have a cellphone and internet connection: Please do the following:
1. Go out at sunset and look west, Venus and Jupiter pop out of the twilight even before the sky fades completely black. The two brilliant planets surrounded by evening blue is a beautiful sight if you go out at the same time tomorrow. The view improves because Venus and Jupiter are converging in Mid-February, they are about 20 degrees apart by the end of the month the angle narrows to only 10 degrees. So close that you can hide them together behind your outstretched palm their combined beauty grows each night as the distance between them shrinks. A special night to look is Saturday February 25th when the crescent moon moves in to form a slender heavenly triangle with Venus, Jupiter, and the moon as vertices. One night later Sunday February 26th it happens again, this arrangement will be visible all around the world from city and countryside alike. The moon, Venus and Jupiter are the brightest objects in the night sky. Together they can shine through urban lights, fog and even some clouds. After hopping from Venus to Jupiter in the late February the moon exits stage left but the show is far from over. In March Venus and Jupiter will continue their relentless convergence until on March 12th and 13th the duo lies only 3 degrees apart a spectacular double beacon and the sunset sky.
Now you will be able to hide them together behind a pair of outstretched fingertips. There is something mesmerizing about stars and planets bunched together in this way and no you are not imagining things when it happens to you the phenomenon is based on the anatomy of the human eye.

How testosterone affects the male body?
A. Regulating the menstrual cycle
B. Stimulating milk production
C. Deepening the voice
D. Triggering ovulation