E3-E6 Flashcards
Combustion
releasing the energy stored in GAS COAL OR FOOD
What does combustion require? release? products
OXYGEN
ENERGY! (EXOTHERMIC0
CO2 AND H2O
What happens during combustion to original chem bonds
ORIG BONDS ARE BROKEN
ATOMS ARE RE-ARRANGED
NEW CHEM BONDS ARE FORMED
Which bonds are in high energy? which are low in energy?
importance
C-H in high energy
C-O and H-O in low energy
The potential energy of products IS LOWER than potential energy of reactants
forms of energy in combustion reaction
Radiant Energy! (HEAT AND LIGHT FROM FLAME)
Kinetic energy (increases due to temp)
Kinetic energy transferred as heat (warm-> cool)
Heat of Combustion
Amount of energy releassed when something burns
Heat of combustion in
exothermic
endowthermic
NEGATIVE!!!!!!!!!!!! (-_)
POSITIVE!!!!!!!!!!!!!(_/-)
fIRST LAW OF THERMO
Energy cant be creaated or destroyed-> energy changed? lost to surroundings
how to assess energy in a chemical reacction
CALORIMETER
Calorimeter in water
Energy is transferred as heat to surrounding water
be recording temp change of water w a thrermomenter! you can get the energy that was transferred
IT IS CRUDE
How to make advanced calorimeter
INSULATION!
WHAT IS THE STANDARD HEAT OF FORMATION
ENERGY CHANGE FOR THE FORMATION OF A COMPROUND FROM ITS ELEMENTS IN standard comdition
heat of formation for an element
ZERO
Hess’s Law
∆ r H = ∑n∆ f H° products – ∑n∆ f H° reactants
What does the hess formula work for
ANY REACTION
hOW TO USE HESSs Law
- Know Products-Reactants
- Re write the formula and REMEMBER MOLS
- Expand with compound heat of formation
- Simplify both sides
- Subtract and CHECK AGAIN
- Does it make sense to get positive or negative answer? ENDO OR EXO
How to get energy per mole
DIVIDE BY MOLS
What does nucleus contain
Protons + and Neutrons (neutral)
Atomic number
of protons
Mass number
PROTONS-#NEUTRONS
A mid X
Z
X= element symbol A= mass number (protons+neutrons) Z= atomic number (protons)
How to calculate neutrons!
Mass- protons
Isotope
neutrons?
protons?
sO WHAT CHANGES DURING NUCLEAR NOTATION
Version of an element with diff # of neturons
SAME # OF PROTONS (bc if not they wouldnt be same element)
The atomic # should be same, but mass number be different in isotopes!
beryllium 9 location
9
4
beryllium 9 location
9 Be
4
Nuclear force
attractive force between protons-neutrons and neutrons-neutrons
electrical force
repulsivee force between protons (LIKE FORCE REPEL)
What makes nuceleus stable
low neutrons?
Neutrons lessen repulsive force between protons (glue)
RADIOACTIVE DECAY BC NUCLEUS UNSTABLE
Radioactive decay
A spontaneous chane in which an unstable nucleus emits radiation
What are the 3 types of radiation
Alpha
Beta
Gamma
Alpha Decay
NUCELUS BRAKS AND GIVES ALPHA PARTICLES
A
Alpha Particles (WHICH ELEMENT?)
are nuclei that c ontain 2 portons and 2 neutrons with charge 2+!!!!
THEY CONTAIN HELIUM!!!!!!!!!!!!!!!!!
ALPHA DECAY
- KNOW THAT ATOMIC NUMBER AND MASS NUMBER HAS TO REMAIN THE SAME
- Helium! 4H2
- Subtract the top and btottom numbers until they are even!
Beta Decay
Nucleus breaking down to give beta particles stream
What are beta particles represented as
ELECTRONS!!! 0E-1
How to rperesent electrons in beta decay
CHECK SCI 30 BOOK
Gamma Decay
-EMR! NO MASS OR CHARGE
How to do gamma decay questions?
ALL NUMBERS MUST EQUAL INITIAL !
ALPHA BETA AND GAMMA ARE ALL WHAT?
IONIZING PARTICLES!
Alpha beta gamma
- easiest to shield?
- which go through dense materials?
- hardest to sheild?
ALPHA BC LARGEST
BETA!
GAMMA needs concrete etc
Fusion- energy?STARS
Joining of two small nuclei to form a larger nucleus!
YES IT DOES RELEASE ENERGY IN THE PROCESS
FUSION IS HOW STARS ARE CREATED
fUSION HAPPENS WHERE?
STARS
What does fusion require!
High temp
high pressure
Called Hot fusion
Cold fusion
If fusiion could happen at lower temp we could use for energy
Deuteriukm
Foundin seawater can enable cold fusion- make it renewable source of energy
Fission
TO BREAK APART
SPLLITTI8NG OF ONE NUCLEUS TO FORM SMALLER NUCLEI WHILE RELEASING ENERGY!
WHERE WAS FISSIONO RIGNATED
Atomic bombs
CANDU
Canadian Deuterium Uranium
ReactoR
Nuclear reactor that gen electricity!
NUCLEAR PROCESSES
Kinetic energy of products heats water
high pressure steam turns turbines
spin generators produce electricity
How to refuce electricity output?
Put in Less fuel! ! it is the three neutrons that are produced after the U-235 reaction that go onto produce more fission reactions
CONTROL THOSE NEUTRONS THAT KICK START THOSE REACTIONS!!!
What is a chain reaaction?
Uncontrolled fisison releases energy so rapidly (leads to nuclear meltdown)
Control rods
These rods absorb neutrons! rhwy CONTROL THE RATE OF A FISSION REACTION
raising control rods (faster reaction) lowering rods (slower reactions)
How to slow down neutrons
How to contrl
Heavy water w deuterium (moderator to slow neutrosn)
CONTROL RODS!
WHAT SLOWS NEUTRONS DOWN
HIGHER DENSITY OF HEAVY WATER!!!! (containign deuterium)
nuclear waste
storage
u-235 fision creates ionizing radition for years!
- first stored in water for a few years (war=ter absorbs thermal energy and sheilds radiation)
- then moved to concrete cansiters above ground
how can small pellet of uranium be equal to so much fossil fuels
Einstein: mass can be converted into energy!
\when mass changes between reactants and products?
result of mass being conveted to energy
what commodity cant be created or destroyed?
ENERGY!
Change in mass change ine ernegy formula?
E=MC^2
What does E=MC^2 MEAN
ANy change in mass= mass converted to energy!
E=MC^2 what is M
so if M disappears?
Sum of kinetic potential and mass ernegy!
it became enrguy!
e=mc^2 what is e
change in energy!
How to calc change in mass between reactants and product?? fr
PRODUCDTS-REACTANTS
How to tell if energy reaction exo or endo? fr
if it is negative
What must you awlays watch out for
MOLS!
What is nucleons or mass number
Neutrons+protons
what changes in nuclear notation
the mass number (top numver)
BOTTOM STAYS THE SAME
Fission reaction trade mark
one thing splits into 3/4
What does fission create
2 NUCLEI AND 3 NEUTRONS
WHAT IS CANDU
FISSION@
FUSION REACTION
Two things come together!
do nuclear plants create particualtesq
NO!
MOST ENERGY REACTIONS
E=MC2
