Okay, I'll stop.
Today's Mission:
Read
p. 502-509
1.
On Earth, in what states does matter
exist?
2.
Explain why solids have definite
shapes.
3.
Why are liquids able to flow and
change shape?
4.
Explain why liquids do not expand to
fill a container, but gases do.
5.
Describe the movement of gas particles.
6.
Explain why gases can be compressed.
7.
List the states in order of attractive
forces between particles.
8.
Create a table with the headings,
“State”, “Properties” and “Degree of Disorder.”
Fill in the table.
9.
What are the two main factors that
determine the state of a substance?
10.
Describe how electrostatic attraction
holds together an ionic compound.
11.
Describe how dipole-dipole forces
occur between particles of HCl.
12.
What attractive forces form between
neutral particles? Name and describe
this force.
13.
Create a table with the headings,
“Type of Motion”, “Diagram” and “States that Employ this Motion.”
14.
How are temperature and kinetic energy
related?
15.
Explain why heating a substance causes
a change of state.
16.
List the five properties that
distinguish gases from solids or liquids.
17.
What makes a gas ideal?
18.
Summarize in a list the five
assumptions of the Kinetic Molecular Theory.
19.
p. 506 # 6, 8 – 10, 14
20.
What is the definition of
pressure? What equation is used to
calculate pressure? What is the SI unit
for pressure?
21.
Explain how Toricelli’s apparatus
worked.
22.
What happens to atmospheric pressure
as you ascend a mountain?
23.
What is standard atmospheric
pressure?
24.
Fill in the blanks: 760 mmHg = __________ torr = __________atm =
__________ kPa
25.
Read through Table 11.3 on p.509. Have you ever used any of the instruments
listed in the table?
26.
p. 510 # 9
Answers:
1. solid, liquid, gas
2. Particles of a solid are held together by strong attractive forces; thus, the particles are unable to move past each other and are "stuck" in position.
3. Particles of a liquid are not held quite as tightly as in a solid and can move past each other.
4. Particles of a liquid are arranged quite close to one another and have fairly strong attractive forces between them, which allows them to flow to take to shape of the container. Gas particles, due to their energetic nature, are quite far apart and have weak attractive forces between them, which allows them to move away from each other and fill the container.
5. Gas particles can move rapidly in three dimensions. If they strike an object (like a container wall), they bounce off and go in another direction.
6. Gases have large spaces between particles.
7. From least to most attractive forces between particles: gas, liquid, solid.
8. Solid - large attractive forces between particles, particles are stuck in position; low degree of disorder
Liquid - medium attractive forces between particles, particles can flow past each other; medium degree of disorder
Gas - weak attractive forces between particles, particles move quickly about and bounce off of objects; high degree of disorder
9. forces holding the particles together; kinetic energy of the particles
10. oppositely charged ions are attracted to each other
11. see the "Student Questions" below
12. see the "Student Questions" below
13. Vibration - see Fig 11.2 (p.504) - solid/liquid/gas
Rotation - see Fig 11.3 (p.504) - liquid/gas
Translation - see Fig 11.4 (p.504) - gas
14. Temperature is a measure of the average kinetic energy of the particles in a sample of a substance.
15. Heating a substance increases the kinetic energy of the particles in the sample. This allows the particles to have greater range of motion due to decreased forces of attraction.
16. Gases (i) are compressible, (ii) expand with increasing temperature, (iii) have very low viscosity, (iv) have very low density, (v) are miscible.
17. Ideal Gas = a gas that has particles with mass but no volume or forces of attraction between them.
18. see p. 505 - top of the page
19. p. 506 #6, 8-10, 14
#6 The He particles escape through the pores of the balloon, leaving an inadequate amount of He in the balloon to overcome the mass of the balloon and make it float.
#8 Gases expand when heated, thereby decreasing the gases density. When the gas is trapped in the hot air balloon, it gives the balloon lift as it floats up through the more dense air near the ground.
#9 As the gas particles move around and strike the sides of the ball, it causes the plastic casing to be pushed outward.
#10 (a) Gas is compressible, (b) Gas will expand to fill its container and gas has a low density, (c) Gas will expand to fill the home, carrying the heat around the house.
20. P = F/A (force exerted over a certain area)
21. see Fig 11.7 (p.508)
22. it decreases
23. SAP = atmospheric pressure in dry air at 0℃ at sea level
24. see p. 509 (middle of the page, highlighted in green)
25. answers vary
26. p. 510 #9 in each case, I have shown the correctly rounded number, with the non-rounded number (to 3 decimal places) in brackets (a) 363 kPa (362.743), (b) 100 kPa (102.658), (c) 1.39 atm (1.395), (d) 63 000 Pa (62 661.513)
Student Questions:
1. Can you go over #11?
A dipole-dipole force operates between two polar molecules. Recall that polar molecules have a slight positive end and a slight negative end. When two polar molecules are in close proximity to each other, the slightly positive end of one molecule is attracted to the slightly negative end of its neighbour. This attraction is called a dipole-dipole force.
2. Can you go over #12?
Non-polar molecules can also exhibit intermolecular forces of attraction (ie, forces of attraction between molecules). Although non-polar molecules do not have permanent slightly positive and slightly negative ends, they can still be attracted to each other via London forces.
Every substance contains electrons. Typically the electrons are distributed evenly around the molecule (fig #1). However, occasionally the electrons may bunch up in one region. This is called an instantaneous dipole, because for an instant one side of the molecule has a very, very slight negative charge due to the "bunched-up" electrons and the other side has a very, very slight positive charge due to the relative lack of electrons (fig #2). A neighbouring molecule will respond to the shift in electron density in the first molecule by mirroring with its electrons, creating an induced dipole (fig #3). The attraction between the 𝛿𝛿+ end of one molecule and the 𝛿𝛿- end of its neighbour is the London force.
A dipole-dipole force operates between two polar molecules. Recall that polar molecules have a slight positive end and a slight negative end. When two polar molecules are in close proximity to each other, the slightly positive end of one molecule is attracted to the slightly negative end of its neighbour. This attraction is called a dipole-dipole force.
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2. Can you go over #12?
Non-polar molecules can also exhibit intermolecular forces of attraction (ie, forces of attraction between molecules). Although non-polar molecules do not have permanent slightly positive and slightly negative ends, they can still be attracted to each other via London forces.
Every substance contains electrons. Typically the electrons are distributed evenly around the molecule (fig #1). However, occasionally the electrons may bunch up in one region. This is called an instantaneous dipole, because for an instant one side of the molecule has a very, very slight negative charge due to the "bunched-up" electrons and the other side has a very, very slight positive charge due to the relative lack of electrons (fig #2). A neighbouring molecule will respond to the shift in electron density in the first molecule by mirroring with its electrons, creating an induced dipole (fig #3). The attraction between the 𝛿𝛿+ end of one molecule and the 𝛿𝛿- end of its neighbour is the London force.
