Unit 3 - Chemistry in Society Flashcards
(48 cards)
Simple distillation steps
- Place the liquid and dissolved solid into the flask
- Evaporate the liquid by heating
- Use a thermometer blocking the top of the tube to monitor the temperature
- Direct the vapour down a side pipe with a condenser
- Use running tap water flowing through the condenser
- Collect the condensed liquid in a beaker
- Left with solid crystals in the flask and liquid in the beaker
Factors influencing sustainable industrial process design
- availability
- sustainability
- cost
- opportunities for recycling
- energy requirements
- marketability of biproducts
- product yeild
Environment considerations for industrial process design
- minimizing waste
- avoiding toxic substances
- biodegradable products
Feedstock availability sustainability and cost profit gain and loss
Gain - local availability
Loss - scarcity, transport- safety, cost, environmental
Opportunities for recycling in industrial processes profit gain and loss
Gain - efficiency^, reduce waste
Loss - difficulty separating unreacted stuff makes it inefficient
Energy requirements and Industrial processes profits gain and loss
Gain - exothermic reactions to keep heat in reaction, or even building; catalysts
Loss - reactions needing heat or cooling can be expensive
Use of byproducts in industrial processes profits gain and loss
Gain - selling biproducts or using elsewhere in a process
Loss - toxic biproducts difficult
Product yield in industrial processes profit gain and loss
Gain - high yield is profitable
Loss - low yields need more expensive repetition of reaction
For n=cV volume must be in
LITRES
Mv
V/m
Volume per mole
Relative rate equation
Rate = 1/time
Time from relative rate
Time = 1/relative rate
Collision theory requirements for a reaction
- correct collision geometry
- sufficient energy to reach an activated complex
Effects on rate
- concentration/ pressure
- particle size
- temperature
Energy distribution diagram for lower energy complex
Y axis = no. of molecules
X axis = kinetic energy
Steeper rising limb, peaks sooner and higher, smaller section past the E(A) line
Energy distribution diagram for higher energy complex
Y axis = no. of molecules
X axis = kinetic energy
More gentle rising limb, peaks later, greater section past the E(A) line
Temperature is
The measure of the average kinetic energy of the particles in a substance
The activation energy is
The minimum kinetic energy required by colliding particles before a reaction may occur
Changing concentration, pressure or particle size impacts the reaction rate because
The number of collisions are increased
Change in temperature effects the reaction rate because
Reacting particles have sufficient energy
In an exothermic reaction the products have ____ energy than the reactants because
Less, energy is being released to the surroundings
In the endothermic reaction the enthalpy change is ______ because
Positive, the reactantion gains energy from its surroundings
ΔH =
H(products) - H(reactants)
The activated complex is
A high energy, unstable arrangement of atoms
