C1 Flashcards
law of conservation
total mass of reactants = total mass of products
nano-
Multiplies the unit by 10-9
Symbol is n
micro
Multiplies the unit by 10-6
Symbol is μ.
millli
Multiplies the unit by 10-3.
Symbol is m.
mega
Multiplies the unit by 10 to the power of 6.
This is equivalent to multiplying by 1000000.
Symbol is M.
giga
Multiplies the unit by 10 to the power of 9.
This is equivalent to multiplying by 1000000000.
Symbol is G.
tera
- Multiplies the unit by 10 to
the power of 12. - This is equivalent to
multiplying by
1000000000000. - Symbol is T.
test for hydrogen
- hold a lit splint to a test tube
with a gas - if the gas is hydrogen, then it
will make a squeaky pop
sound - it makes this sound bcs
hydrogen burns rapidly in the
presence of oxygen to give
H2O.
test for oxygen
*put a glowing splint into a test
tube containing a gas.
* if the gas is oxygen, the
splint will relight.
testing for carbon dioxide
*bubble through, or shake
carbon dioxide with, an
aqueous solution of calcium
hydroxide (also called lime
water).
* The solution will turn from
clear to cloudy.
oxidation
addition of oxygen
loss of electrons
reduction
loss of oxygen
gain of electrons
Magnesium + oxygen → magnesium oxide
2Mg + O2 → 2MgO
Iron oxide + carbon monoxide → iron + carbon dioxide
Fe2O3 + 3CO → 2Fe + 3CO2
conservation of energy
energy can be transferred usefully, stored or dissipated, but it cannot be created or destroyed
endothermic
*TAKES IN energy from surroundings
*normally shown through FALL in temperature
exothermic
*GIVES OUT energy to surroundings
*normally shown with RISE in temperature
examples of exothermic
combustion
neutralisation
oxidation
hand warmers
examples of endothermic
thermal decomposition
the reaction between citric acid and sodium bicarbonate
ice packs
sports injury packs
when squeezed forcefully, ammonium nitrate and water mix in the pack, resulting in instant cooling. the speed of this reaction makes these packs ideal for scenarios when ice is not immediately available.
2 requirements for a successful reactions
*reacting particles must collide
*collisions must take place with
sufficient energy (the
activation energy)
what is activation energy?
the MINIMUM amount of energy that reacting particles must have in order for a reaction to occur
What information is contained within reaction profile diagrams?
relative energies of reactants and products
activation energy
overall energy change