Term 1 Flashcards
(59 cards)
1
Q
Matter
A
Anything having mass and volume
2
Q
Mass
A
Amount of matter in a substance
Mass of a matter does not change in the universe
Unit: Kg (Kilograms)
3
Q
Volume
A
Space occupied by a matter
Unit: l (litre)
4
Q
Name the three different states of matter
A
Solid
Liquid
Gas
5
Q
Name a few characteristics of solids
A
Solid: Definite shape and volume. Particles packed tightly in a regular arrangement. Particles can only vibrate.
6
Q
Name a few characteristics of liquids
A
Liquids: No definite shape but has definite volume. Takes the shape of the container. Particles are packed in an irregular and loose arrangement. Particles can vibrate and rotate.
7
Q
Name a few characteristics of gases
A
Gases: no definite shape nor definite volume. It completely occupies its container. Particles are quite far apart and move freely and quickly.
8
Q
The particle model of matter or the kinetic molecular theory of matter
A
- All matter is made up of particles (These particles are either atoms or molecules)
- Matter exists in three different states (solid, liquid and gas)
- Particles are in constant motion
- Particles may attract or repel each other
- Particles move faster as temperature increases
- Particles may collide with each other
9
Q
Temperature
A
Is the measure of average kinetic energy
10
Q
Name a few physical properties of matter
A
- Strength: The ability to withstand a force applied
- Thermal and electrical conductivity: The ability to conduct heat and electricity
- Brittleness: How easily it breaks or fractures when subjected to stress or force
- Malleability: quality of a matter that can be shaped into something else
- Ductility: Ability to be drawn without fractures
- Magnetism: Ability to be pulled by a magnet
- Solubility: is the maximum amount of solute which can be dissolved in a given solvent
11
Q
Density
A
Mass of a matter per unit volume
Formula: d=m over v
d = g/cm3
m (mass) = grams
v (volume) = cm3
12
Q
How many liters of olive oil are 5 kg? (density of oil = 0.9 g/ml)
A
- 5 Kg = 5 * 1 000 = 5 000 g
- d = m over v
- 0.9 = 5 000 over V
- V = 5 555.56 ml
- V = 5.56 litres
13
Q
Melting point
A
The temperature at which the solid and liquid phases of a substance are at equilibrium
14
Q
Solid to Gas
A
Sublimation
15
Q
Gas to Solid
A
Deposition
16
Q
Boiling point
A
The temperature at which the vapour pressure of a substance equals atmospheric pressure
17
Q
Classification of matter
A
Matter =
- Pure substances - Mixtures
- Elements and Compounds - Homogeneous and Heterogeneous mixtures
18
Q
Element
A
-Is a pure substance that contains only one type of atom
- Cannot be broken down into simpler substances by physical or chemical means
- Examples: Magnesium, Gold, etc. (all elements are on the periodic table)
- Types of elements: Metals, Non-metals and Metalloids (Semi-metals)
-
19
Q
Characteristics of metals
A
- Good conductors
- Lustrous
- Malleable
- Ductile
- High Melting Point
20
Q
Characteristics of non-metals
A
- Do not conduct electricity except for graphite. (Graphite can conduct electricity)
- Brittle when solid
- Not lustrous
- Low density
- Low melting point
21
Q
Characteristics of metalloids (Semi-metals)
A
- Semi-conductors
- Examples: Boron, silicon, etc.
22
Q
Compounds
A
- Are pure substances that are composed of 2 or more atoms
- Can be broken down into its components which are elements by CHEMICAL means ONLY
22
Q
Ways to seperate compounds
A
- Heat
- Electrolysis
23
Q
Mixture
A
Is the combination of two or more substances formed by physical means only
24
Heterogeneous mixtures
Does not have the same composition throughout. Examples: Water-Oil, Milky-Water, etc.
25
Homogeneous mixtures
- Have the same composition throughout
- Examples: Salty water, Sugar-water, AIR, tap water, etc.
26
Solutions are composed of ... and ...
solvents and solute
27
The two types of Heterogeneous mixtures
- Suspension
- Emulsion
28
Suspension
Is a heterogeneous mixture in which a solid is dispersed in a liquid heterogeneously.
Examples: Sand-water, Saw dust-water.
29
Emulsion
A heterogeneous mixture in which a liquid is dispersed in a liquid heterogeneously
Examples: Oil-water, Gasoline-water, etc.
30
Hot air = large volume and low density
(Lighter)
Cold air = smaller volume and high density
(Heavy)
31
Attractional/Intermolecular forces
Intermolecular forces are the forces of attraction between molecules.
## Footnote
If intermolecular forces are strong then it takes more time and energy to weaken and break those forces between particles. This process is shown by a straight line, which indicates melting point and boiling point, on a cooling or heating curve. The straight line is drawn there to tell us that it took x amount of time to weaken/break the intermolecular/attractional forces between the particles.
Strong intermolecular forces = solid
Weak intermolecular forces = liquid or gas
32
Relative Atomic Mass
Mass of an atom in comparison to a Carbon-12 atom is called relative atomic mass.
33
Isotopes
Atoms of the same element with the SAME number of PROTONS but DIFFERENT number of NEUTRONS are called isotopes.
34
Formula to calculate average atomic mass
(mass of first isotope.isotope% + mass of second isotope.isotope% + ...) over 100
35
Electron Configuration
The way electrons are arranged in an atom
## Footnote
Electrons spin around the nucleus at certain energy levels (shells).
There can be a max. of 7 shells in an atom.
The nearest shell to the nucleus has the lowest energy.
36
The formula to find the max. no. of electrons in an atoms
2nsquared
n = shell number
Example: Find the max. no. of electrons in the first shell.
- 2n^2
- 2.(1^2)
- 2 electrons
37
Orbital
The regions in a shell where electrons can exist are called orbitals
## Footnote
An orbital can have a max. of 2 electrons in oppostie spin, due to Pauli's Exclusion Principle.
38
Aufbau Principle
States that electrons are filled in atomic orbitals in an order of increasing energy levels. (Ascending order(smallest to biggest))
39
Hund's Rule
Electrons fill the same energy level orbitals one by one first and then they start to pair
40
Electron Configuration for Berylium (Be4)
1s^2 2s^2
## Footnote
Need to know how to draw Aufbau diagram (remember to label energy as E by the arrow) !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
41
4s<3d
Important. Must remember.
41
Electron Configuration for Scandium
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^1
42
Condensed electron configuration
Example:
For Chlorine (Cl17): [Ne] 3s^2 3p^5
43
Know how to do atomic notation
And those other questions like if atom X^-1 and Y^2 have the same number of protons then .........
44
Valence shell
The outermost energy level of an atom
45
Valence electrons
The total number of electrons in the last shell.
REMEMBER to include all the orbitals FOR EXAMPLE, 1s^2 2s^2 2p^6. The valence electron no. would be 2+6= 8.
46
Core electrons
Core electrons are all the electrons in inner shells (lower energy levels) that are not part of the outermost shell.
47
Group 1: gives 1 electron so charge would be +1
Group 2: gives 2 electrons so charge would +2
Group 17: takes 1 electron so charge would be -1
Oxygen takes 2 electrons so its charge would be -2 (btw this does not apply to the entire group of oxygen as its group is unstable. This is for OXYGEN ONLY!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!)
Important!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
48
Dalton's Atomic Theory
1. All matter is made up of tiny particles called atoms shaped like billiard balls.
2. The atoms of the same elements are identical; atoms of different elements are different. (different atoms different matter)
3. Compounds are formed when atoms are combined in a specific ratio (The law of multiple relationships)
4. Atoms cannot be created or destroyed or divided in a chemical process.
## Footnote
You guys can remember it as DALS (This is so bad. I know)
D = Destoyed, Divided, created
A = Atoms are solid spheres like billiard balls
L = Law of multiple relationships
S = Same elements, Same matter. Different elements, Different matter
49
Thomson's Atomic Model
1. Atoms are composed of positively and negatively charged particles
2. Protons and electrons occupy an arbitrary (random) position in the sphere
3. An atom looks like a plum pudding, negatively charged electrons are embedded in a positively charged soup.
## Footnote
Thomson had thought that electrons and protons were randomly positioned in an atom, just like in a plum pudding.
50
Rutherford's Atomic Model
1. Atoms composed of mostly empty space.
2. The positively charged atoms called protons are concentrated in a very small volume at the centre. This volume is called the nucleus
3. The nucleus is surrounded by negatively charged electrons of very small mass.
## Footnote
He carried out the Gold Foil experiment.
51
How was the Gold Foil experiment set up?
A thin gold foil was bombarded with alpha particles from a radioactive source (radium).
A fluorescent screen coated with zinc sulfide surrounded the foil to detect the alpha particles by flashing when struck.
## Footnote
Know the labels for the diagram from the textbook
52
What did Rutherford expect would happen when the alpha particles hit the flourescent screen?
The expectation, based on J.J. Thomson’s Plum Pudding Model, was that the alpha particles would pass through with minimal deflection.
53
What did Rutherford observe in his experiment?
Most alpha particles passed through the foil without any deflection. - This suggested that most of the atom is empty space.
Some alpha particles were deflected at small angles.
- This indicated the presence of a positively charged region that repelled the particles.
A few alpha particles bounced back at large angles (even 180°).
- This was a surprising discovery, implying that the positive charge and mass of the atom were concentrated in a very small, dense core.
54
Bohr's Atomic model
1. Electrons move around the nucleus of the atom in one of several energy levels.
2. Electrons with same energy move in the same energy level.
3. The energy levels further from the nucleus have higher energy than the energy levels closer to the nucleus
## Footnote
His model, the planetary atomic model, was identical to the model of the solar system.
The sun was in the middle, just like the nucleus in an atom, and the planets orbit around it, just like the electrons.
55
What did the following people discover/prove (What were their theories?)
1. Lois de Broglie
2. Davisson and G.P Thompson
3. Schrodinger
4. Heisenberg
5. Chadwick
6. Democritus
7. Faraday
1. Electrons have wave properties
2. Confirmed Lois de Broglie theory
3. Formulated the wave mechanical model
4. Uncertainty Principle
5. The neutron
6. Matter consists of indivisible particles
7. Matter hasan electrical nature and consists of a fixed amount of energy.
56
The Uncertainty Principle
It explains the position of electrons.
It states that, "It is impossible to determine both the velocity and position of a particle at the same time."
57
What does "atomos" mean?
Indivisible
