midterm 5 Flashcards
What are the properties of metals? (Section 21-1)
Malleability, Opacity, Thermal Conductivity, Reflectivity, High melting temperature, Electrical conductivity
Why do metals have their properties? (Section 21-3)
High melting temp: strong bonds between atoms making need for a lot of KE to pull apart to liquid.
Electrical Conductivity: Mobile electrons not bound tight, Charges of the metal move around electrical current.
Thermal Conductivity: electrons responsible for electrical conductivity also carry KE energy which is heat energy.
Malleability: fluid like electrons act like lubricant between nuclei
Opacity: absorb radiation over the entire visible region, as well as infrared and UV.
Reflectivity: mobility of electrons allow them to easily interact with light waves
There will be a question about conductivity of ionic compounds (Section 22-4 )
Materials that conduct electricity when dissolved in water are called electrolytes
What is an intermolecular force? What is an example of an intermolecular force?
the forces between molecules.
4 types (weak to strong)
-Dispersion, dipole-dipole, hydrogen, covalent.
non-metals: atomic volumes, valence electrons, ionization energy
non-metals: small atomic volumes, many valence electrons, and very high ionization energies
metal is opposite
There will be a question from Section 22-3 ( I will provide a periodic table of the elements on the test.)
study
There is a question on Names of Salts found in section 22-5. How are salts named?
metal first, then non-metal
What is the fundamental concept from chapter 23?
covalent bonding: sharing of electrons
What is an intermolecular force? What is an example of an intermolecular force?
the forces between molecules.
Intermolecular: between molecules (intra is within)
weak
Inter-molecular forces are forces which mediate interaction between molecules
4 types (weak to strong)
-Dispersion, dipole-dipole, hydrogen, covalent.
What fats are liquid at room temperature?
unsaturated fats. oils.
What fats are the best and worst for your health in order?
unsaturated
saturated
trans
What elements are used to make a silicate ion?
single Si atom surrounded by 4 O atoms
There will be a question from Figure 23.7 Relative strengths of molecular interactions.
C6H12O6
What is fission?
A nuclear reaction in which an atomic
How do scientist know about the different layers of the Earth?
By using half life “T1/2”
time required for 1/2 of the sample to decay
Why do saturated and unsaturated fats have different melting temperatures?
Bent: unsaturated fats, kink makes molecule have lower melting/boiling temp.
Straight: saturated fats, high m/b temp.
Shorter the chain, the lower m/b temp
There will three questions from table 24.1.
nutrition.poly is better than mono
You should know how minerals correspond to type of structure.
294
Why do the silicate minerals form different shapes?
morphology
What is fusion?
Combining small mass nuclei to make more massive nuclei.
A nuclear reaction in which nuclei combine to form more massive nuclei with the simultaneous release of energy
What is fission?
start with very large atoms and split them into smaller atoms.
A nuclear reaction in which an atomic nucleus, especially a heavy nucleus such as an isotope of uranium, splits into two fragments of comparable mass, releasing energy.
What is radioactive decay? What are all the types of radioactive decay?
Radioactive decay- changes a nucleus from a high energy state to a lower energy state.
Alpha, Beta, Gamma
semiconductors are doped.. youtube
Semiconductors: A solid crystalline substance, such a germanium or silicon, that conducts electricity better than insulators, but not as well as metals. Unlike metals, they become better conductors as their temperature increases.
Doping: inject a foreign substance in order to improve performance
Two Types of Doping:
N-Type: take pure silicon and inject the small amount of an element with five valence electrons - like phosphorus. Brings an extra electron. The semiconductor has more mobile charges - so it conducts current better.
P-Type: an element with only three valence electrons is added to the lass. Like boron. This creates a hole - a place where there should be an electron but there isn’t. This still increases the conductivity of the semiconductor because the electrons can move into it. Hole = lack of an electron. Acts as a positive charge.
*Both dopings are neutral charges
What are all the ways to get energy from the nucleus of an atom?
Fission and Fusion.
fission: split big
fusion: combine small
Study Figure 25.1 it is the most important figure in all of physical science.
graph thing
Fe is lowest
What causes the Earth’s magnetic field?
electric currents in the conductive material of core, created by convection currents due to heat escaping. The Coriolis force, from Earth’s spin, causes swirling whirlpools. This flow of liquid iron generates electric currents, which in turn produce magnetic fields.
What are the predominate materials of the Earth’s crust, mantle, and core?
crust: granitic continental crust and basaltic oceanic crust
mantle: peridotite
core: iron
Where are the Earth’s most and least dense materials?
Most dense: in middle/core
Least: outside/crust
What are the mechanical layers of the Earth?
lithosphere, asthenosphere, mesosphere, outer core, and inner core
What are the compositional layers of the Earth?
crust, mantle, core
Alpha Decay
helium nucleus emitted from a heavy nucleus,
radioactive decay of an atomic nucleus by emission of an alpha particle
Beta Decay
Process that changes neutrons into protons and protons into neutrons.
charge must be conserved.
Radioactive decay of an atomic nucleus accompanied by emission of a beta particle.
Gamma Decay
Light.
Photon is emitted when protons and neutrons shift from one energy level to a lower level.
