Units 24-25 Flashcards
6 Examples of high fat substances
- shortening
- butter
- stick margarine
- olive oil
- canola oil
- “buttery spread”
True or False: Melting point behavior - whether the material melts all at once or over time - is dependent on the purity of a material.
True
True or False: Pure substances change physical state at a single temperature
True
What is the opposite of a pure substance?
Matter that is a mixture of multiple substances
Are the 6 examples of fatty acids pure substances or not?
Not. They’re mixtures.
What is the difference between a fat or an oil?
Fats are solid at room temperature
Oils are liquid at room temperature
Why are oils thought to be a little healthier than fats?
Because they aren’t solid at room temperature, so they can’t clog your arteries.
What is the molecule that all fats and acids contain?
glycerol
Triglyceride
A molecule containing three acids hooked to glycerol
True or False: Most fats and oils are triglycerides
True
What does the term “saturated” mean?
It contains the maximum possible number of H atoms.
True or False: Unsaturated fatty acids have a hard time packing tightly together in the solid state.
True.
There are kinks caused by double bonds.
What type of fat should you avoid at all costs?
Trans-fatty acids!
They do soooo much damage to your body, even replacing healthy fats in your brain to cause dementia.
What types of fats are good for you?
Monounsaturated fats
Polyunsaturated fats.
True or False: Saturated fats belong to the “bad guys” nutrition.
True
Crystalline
Solid matter where the constituent particles are arranged in an orderly, repetitive pattern.
Fat
A substance that is solid at room temperature and that does not dissolve in water but can dissolve in hydrocarbon liquids.
Fatty acids
A molecule with a long hydrocarbon tail and an acid group –COOH at the other end.
Glycerol
A small molecule that contains only three carbons and reacts easily with molecules that belong to the family of organic acids
Monounsaturated fats
Fats containing fatty acids with a single double bond.
Morphology
The form or structure of a material.
Related to chemical binding properties
Oil
A substance that is liquid at room temperature and that does not dissolve in water but can dissolve in hydrocarbon liquids.
Polyunsaturated fats
Fats containing fatty acids with two or more double bonds.
Saturated Fatty acids
A fatty acid with the maximum possible number of H atoms, which means there are no double bonds between the carbons in the carbon chain.
Trans fatty acids
A fatty acid with at least one double bond between the carbon atoms in the carbon chain. Where the double bond occurs, the hydrogen atoms have switched places to be on opposite sides of each other. This removes the kink in the molecule due to the double bond.
Triglyceride
A large molecule created by reacting three fatty acids with glycerol.
Unsaturated fatty acids
A fatty acid with fewer than the maximum possible number of H atoms, which means there is at least one double bond between the carbons in the carbon chain.
Why are fats solid at room temperature?
Because they have stronger forces between the molecules
What are fats and oils made up of?
2 molecules: Glycerol and a fatty acid of some kind
What are fatty acids made of?
A long hydrocarbon chain (fat portion)
with a -COOH (acid portion) on the end.
What is the fat portion of a fatty acid made of?
hydrocarbon chain
What is the acid portion of a fatty acid made of?
-COOH
True or False: If a double bond between carbon atoms occurs, the number of hydrogen atoms decreases by 2
True
How many double bonds (between carbon) does a monounsaturated fat have?
1
How many double bonds (between carbon) does a polyunsaturated fat have?
more than 1
Is the melting temperature of mono and polyunsaturated fats generally lower or higher than saturated fats?
lower
Why is a trans fat different than an unsaturated fat?
It still has the double bond kink, but the molecules have been rearranged so it has the saturated zigzag pattern. This allows it to stack better.
TERRIBLE for you
Hydrogenated oils
Manufactured oils that WERE unsaturated with double bonds, but have been infused with hydrogen so now they’re saturated.
What kinds of foods have trans fats?
Margarine
Microwaveable popcorn
Processed foods
True or False: Minerals have high melting temperatures
True
QCD
Quantum Chromo-dynamics
True or False: Even though opposites attract and like charges repel each other, SOMEHOW, there is a force holding like positive charges together in a small, dense area within the nucleus of an atom.
TRUE
Strong nuclear force
True or False: Some of the mass of protons and neutrons becomes binding energy (strong nuclear force) within the nucleus of an atom.
True
Why is radioactivity dangerous to organic life?
Because the enormous amount of energy from a single radioactive particle can disrupt millions of the chemical bonds in living tissues.
When does the strong force reach its maximum range of influence?
At a distance the diameter of an iron atom nucleus
True or False: A nucleus will only form when the forces holding it together are larger than the forces pulling it apart.
True
True or False: Nucleons in different nuclei have different amounts of mass.
True
What did Einstein assume about splitting atoms?
If you either combine small nuclei to make a larger nucleus OR split the largest nuclei to make smaller ones, the mass that the protons and neutrons lose in the process will be released as ENERGY.
Fusion
1 of 2 nuclear techniques.
Combining small mass nuclei to make a more massive nuclei.
What energy is added to make fusion happen?
Heat energy.
Heat that speeds up the nuclei so they get close enough for the strong force to take over and fuse.
What is the way we create enormous amounts of heat energy required to make fusion possible? What device can control several million degrees of heat?
Hydrogen bombs
Fission
The second of 2 nuclear techniques:
Starting with a large atom and splitting it into smaller atoms.
How does a nuclear chain reaction work?
Fissions create split atoms and release free neutrons. Neutrons are absorbed by another uranium atom, causing THAT to split as it becomes unstable.
Fissions triggering fissions.
Why are cadmium and boron used to absorb additional neutrons in nuclear fission reactions?
Because each fission reaction creates more than one free flowing neutron. This would create an insane number of unstable reactions.
Boron and cadmium are both good at absorbing additional neutrons, so they are used to control the reaction rate by being moved into or out of the fuel.
Why is nuclear energy via fission difficult?
- The elements best suited for production are not abundant in nature.
- When these elements fission they produce radioactive and poisonous elements that have to be handled carefully.
Radioactive decay
Spontaneous disintegration of an unstable nucleus.
It is accompanied by the emission of radiation in alpha/beta particles or gamma rays.
It is a spontaneous process that changes a nucleus from a high energy state to a lower energy state.
What are alpha particles, beta particles, and gamma rays?
Photons
True or False: Spontaneous fission is possible
True
True or False: Half lives are a fixed amount of time.
True
True or False: The nucleus of an atom is described as a wave.
True
True or False: The nucleus emits waves of energy
True
Alpha decay
Radioactive decay process in which an alpha particle is emitted.
Alpha particle
Helium-4 nucleus.
Beta decay
Radioactive decay process involving a neutrino and an electron or positron.
Beta particle
an electron
Control rods
Rods used in a nuclear reaction to absorb neutrons and slow or stop the fission reactions.
Daughter
Elements produced in a radioactive decay process. The daughter elements are found on the right side of a nuclear reaction equation.
Fuel rods
Rods of fissile material, usually uranium-235, but plutonium also can be used.
Gamma decay
Radioactive decay process in which a gamma ray is emitted.
Gamma ray
High-energy, high-frequency electromagnetic radiation.
Isotope
An atom with the same number of protons but a different number of neutrons.
Mass number
The total number of protons and neutrons in a nucleus.
Moderator
A material used to slow down neutrons, which increases the likelihood of the neutron being absorbed by the large nucleus.
Nucleon
A particle found in the nucleus—proton or neutron.
Parent
Elements that decay into a different element in a nuclear reaction. The parent elements are found on the left side of a nuclear reaction equation.
Positron
A positive electron.
Why are nuclear reactions stronger than electromagnetic reactions?
(nucleus vs. electron reactions)
Because the force holding the nucleus together is way stronger than the electromagnetic force (strong force).
What force opposes the electromagnetic force?
Strong force