February 2012
53 posts
3 tags
Woah...
Tumblr’s changed
I hate checking my university email for offers.
quirkbiscuits:
It always goes like this.
Anonymous asked: It's like a Chemistry Revision Guide here ! x)
3 tags
Upgrade SLR or Macbook Pro?
Can’t decide T_T Just saw the D5100 for a great price… but I need a new laptop for Uni this year.
Decision, decisions, decisions…
2 tags
Eurgh...
Keep mixing up the definitions of ‘translation’ and ‘translocation’ -_-
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20 tags
I need opinions from other photographers
christianislost:
Canon or Nikon and why?
I’m having trouble deciding between a Canon 5d or a Nikon D7000
Weight wise, Nikon’s are heavier than Canon’s. I own a Nikon & I feel that it’s sturdy in hand due to its weight. My uncle owns the D7000 & I can say that the image quality is amazing, it’s quite heavy too! I sound like I’m being biased but in my...
reenymoargh:
Maths = worst exam ever.
I’m screwed. xD
So damn true…
12 tags
Brain is dying.
reenymoargh:
I also really hate how my parents are in bed by like…9pm, 10pm at the very latest.
Makes me feel like I should be sneaking about in the dark downstairs to avoid monsters when I go down for a bottle of water.
Which reminds me of the beef bourguignon dad cooked from scratch tonight. Delicious. ;_;
Nomnomnom. Beef bourguignon! We need to make some when we live together & add...
9 tags
10 tags
So according to my sister...
Wearing dark grey super skinny jeans, over-sized light wash denim button shirt, black vest top, chestnut ankle boots & a tan skinny belt isn’t casual at all. ==
Came across a photo on Facebook.
Lucky lucky lucky girl, engaged with a Tiffany’s engagement ring ><
Chemistry, Unit 1: Revision (6)
Percentage yield:
PY = actual yield/theoretical yield x 100
Calculate no. of moles (n = m/GFM)
Calculate mass (m = n x GFM)
Use % yield equation
Atom economy:
AE = mass of desired products/total mass of reactants x 100
Avogadro & the Mole:
“6.02 x 10^23”
Calculate no. of moles
Multiply no. of moles by ‘6.02 x 10^23’
Volumetric Titration:
To measure...
Chemistry, Unit 1: Revision (5)
Bond enthalpy:
? - Energy required to break and make one mole of bonds.
Bond breaking = Endothermic process (positive)
Bond making = Exothermic process (negative)
Enthalpy of combustion:
? - Heat energy given out when one of a substance burns into oxygen.
To calculate Eh:
Eh = cm ΔT
ΔH = Eh/n
Hess’ Law:
? - Overall enthalpy change will be the same whichever route taken.
ΔH1...
Chemistry, Unit 1: Revision (4)
Activation Energy & Reaction Pathway:
The higher the Ea, the higher the barrier and slower the reaction.
To calculate Ea:
Calculate ΔH (Hp - Hr)
Ea = Heigher of Ea - ΔH
Activation energy = Energy needed for colliding particles to form activated complex.
Effect of catalysts:
? - Speeds up a chemical reaction but is left unchanged in the end.
2 types of catalysts:
Homogeneous - Same...
Chemistry, Unit 1: Revision (3)
Effect of temperature on reaction rate:
Temperature = Measure of average kinetic energy of particles in energy.
Activation energy = The minimum energy required for particles to collide successfully. They also have the potential to react if over this level but don’t always react.
Enthalpy:
? - Measure of energy stored in a chemical.
ΔH - Change in enthalpy
ΔH = Hproducts - Hreactants
...
Chemistry, Unit 1: Revision (2)
Reversible reactions:
Dynamic equilibrium = Forward & reverse reactions continue at the same rate.
Forward reaction - Reaction rate slows down
Reverse reaction - Reaction rate speeds up
Le Chatelier’s Principle = An equilibrium will move to undo any changes imposed upon it.
Changes in condition:
Increase in concentration - Eq will move to remove the substance added which decreases...
Chemistry, Unit 1: Revision (1)
Seven Industrial Processes:
Availability cost & sustainability of feedstock
Opportunities for recycling
Manageability of by-products
Energy requirements
Atom economy or product yield
Environmental Issues:
Avoiding use of production of toxic substances
Minimizing waste
Designing biodegradable products
Calculation Equations:
Mass: n = m/GFM
Moles in solution: n = v x c/1000 (units...
