Intro to Chem Rxns
The LEFT side of a chemical reaction is called____________.
REACTANTS!
H2 + O2 --> H2O
SYNTHESIS! (S)
N2 + H2 --> NH3
(1,3,2)!
Can be stopped by a thick piece of paper!
ALPHA!
The FRACTION of a nucleus that is left after it has taken 3 half-lives?
1/8!
The vocabulary term that refers to reactions that release heat energy when bonds are broken.
EXOTHERMIC REACTION!
KClO3 --> KCl + O2
DECOMPOSITION (D)!
HgO --> Hg + O2
(2,2,1)!
Is NOT considered to be matter?
GAMMA RAYS!
The PERCENTAGE of a nucleus that is left over when 5 half-lives have occurred?
3.125%!
Name 4 of the 6 INDICATORS of a chemical change.
1) Light/heat
2) Color change
3) Gases produced (bubbles)
4) Odor/smell
5) Sound
6) Precipitate forms
CaS + AlF3 --> CaF2 + Al2S3
DOUBLE REPLACEMENT (DR)!
Zn + HCl --> ZnCl2 + H2
(1,2,1,1)!
Beta particle radiation is EQUAL to a 1)_____________ and has a 2)_________________ charge.
1) electron
2) negative
Li-9 has a half-life of 30 years. How many years does it take for 100 grams to decay to 6.25 grams?
120 YEARS!
In every chemical reaction, THREE FACTORS OCCUR! Name TWO THINGS that occur!
1) Bonds are broken
2) Atoms are rearranged
3) New products are formed
C3H8 + O2 --> CO2 + H2O
COMBUSTION (C)!
P4 + O2 --> P2O5
(1,5,2)!
Can be stopped by thick Pb and extremely thick Al?
GAMMA RAYS!
The half-life of Pa-234 is 6.75 days. What mass of a 56 gram sample iwll remain after 27 hours?
3.5 GRAMS!
We can change the rate of CHEMICAL REACTIONS. Name 4 out of the 5 things that can SLOW DOWN chemical reactions.
1) Decrease the temperature!
2) Decrease surface area!
3) Do not add more reactants!
4) Do not agitate!
5) Do not add a catalyst!
MgO + N2 --> Mg3N2 + O2
SINGLE REPLACEMENT (SR)!
C5H12 + O2 --> CO2 + H2O
(1, 8, 5, 6)!
Together called NEUTRON EMISSION REACTIONS, these 2 things releases tons of energy and neutrons.
NUCLEAR FISSION & NUCLEAR FUSION!
There are benefits & risks of nuclear energy! Name TWO BENEFITS and TWO DISADVANTAGES!
Benefits: low-cost to produce, reliable & clean energy source, treat & detect diseases
Risks: high costs to build power plants, high cost to store radioactive waste, causes diseases in excess, accidents!