General Flashcards
At what layer i the atmoshpere is the ozone layer located
stratosphere
How many carbon + oxgyen atoms are in the molecule of the ozone layer
one carbon and three oxygen
What causes the Thinning of the ozone layer
The use of CFS (chlorofluro carbons) in fridges
what are the two types of researches, and their causes
1.pURE rESEARCH: for no reason, only to gain knowledge
2.Applied Research: for solving a specific problem
What the measure of the amount of matter
mass
What are the four types of matter
-
Solid:
- fixed volume
- fixed shape
- tightly packed
-2. Liquid - Gas
- Plasma: ionized gas
What are examples of chemical changes
rust of iron
loss of a silver’s luster
burning wood
what are the three types of physical changes in exothermic molecules?
- Freezing: Liquid to Solid
- condensation: vapor to liquid
- percipitation
What is DEPOSITION
gas –> solid (without going through the liquid stage
What is combustion
Oxygen combines with a substance and produces energy in the form of heat and energy
What the difference between synthesis and decomposition
Synthesis is when two substances combine together to produce a single product
Decomposition is when a compound breaks down to produce two subtances
What are the two types of replacement?
Single replacement: its when atoms of one element in a compund replaces atoms of another element in the same compunds
A+BX –> AX+B
zn + NiCl2 –> ZnCl2 + Ni
Double replacement: its the exchange of ion between two distinct compund
AX+BY –> AY+BX
ZnOH + NiCl –> ZnCl +NiOH
Page 2 in PDF file
What is the mole ration ?
**Mole Ratio **: the ratio between the number of moles of any two substances in a balanced equation
https://youtu.be/4q2elWPfB6A
What the law of MOLES
Molar mass(g/mol) = Mass(g)/Moles(mol)
https://youtu.be/4q2elWPfB6A
Philospher’s ideas and theories about the atom:
Democritus:
1. matter is composed of atoms that moves thru empty spave
2. atoms are solid, homogenus, indestructible and invisible
3. atoms are different in sizes and shapes
4. the size, shape, and movement of the atom determines its properties
Aristotle:
1. Empty space does not exist
2. Matter is made o earth, fire, air, and water
Dalton
1. all matter is composed of extremely small atoms
2. invisible and indestructible
3. *the atoms of a single element are identical in all properties *
4. *atoms in an element are different from atoms in another element
5. different element can combine in simple, integer ratios to form compounds *
6. atoms can be separated, rearranged or combined in chem reactions
By who and how were electrons discovered?
By Thompson through his cathode-ray tube experiment
Sum of Thompson’s atom model(pudding model):
Thomspon: Atoms are a shpere made of uniformly distributed positive charges in which neatively charged electrons((9.11x10*-28) are embedded
What is the unit/numer used to indicate the relaive energy and size of an atomic orbital?
The Principal Quantum Number(n)
Describe the secondary energy levels, total capacity and number of orbitals of energy levels n1-n4
n1 sl= s tc=2 no.orbits: 1
n2 sl=p tc= 6 no.orbits: 3
n3 sl=d tc=10 no.orbits: 5
n4 sl =f tc= 14 no.orbits: 7
1s =2
2s 2p = 2+6 =8
3s 3p 3d = 2+6+10 =18
4s 4p 4d 4f =2+6+10+14 =32
page 4 in PDF file
https://youtu.be/NIwcDnFjj98
Aufbau Prnincle states:
Electrons occupy the lowest energy orbital first, and then move on to occupy the rest
https://youtu.be/SvlDqyV5lXQ
Pauli Exclusion Principle
a maximum of two electrons going in opposite direction can occupy a single atomic orbital
https://youtu.be/bdfir8uT06Q
Hund’s Rule
single electrons with the same spin must occupy equal-energy before addition of electrons with opposite spin in the same orbital
https://youtu.be/SoNIQjW5Zxs
What determines the reactivity of an atom?
The number of valence electrons(electrons on the outermost level of the atom; furthest from nucleus, weakest bond, fastest to react to surrondings)
What is the Lewis Dot Dtructure?
I t represnents the valance electron sublevels in an atom using a systemof symbols of dots
What are the two exception in the electronic configuration rule
Cu: Copper
Cr: Chromium
What dissociates the sunlight?
- glass
- prism
- water molecules