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Question 1

in fuel cells

Why are half cells separated

Answer 1

• The half-cells need to be separated so that electrons can travel between the two half-cells in connecting wires (through the load) and the electrical energy harnessed.
  if there is no serperation of the two half cells, oxidation and reduction would occur together and electrons would not move through the external circuit

Question 2

in fuel cells

Whats the feature that causes the overall movement of h+

Answer 2

• As the electrons enter the cathode, the O2 half-cell becomes negatively charged. The mobile H+ ions are attracted to the cathode from the biomass half-cell and pass through the membrane.
• As electrons leave the anode, the biomass half-cell becomes positively charged. The mobile H+ ions are repelled from the anode and biomass half-cell and pass through the membrane.

Question 3

hygroscopic properties of biodesiel and petrodesiel

Answer 3

· Biodiesel is more hygroscopic than petrodiesel.
· Biodiesel molecules have polar ester groups, which allow for stronger intermolecular forces with the polar water molecules.
· Petrodiesel is predominately non-polar; it has a weaker intermolecular attraction to the polar water molecules than biodiesel.

Question 4

why is aspartmane better to use in soft drinks

Answer 4

While they all have the same energy content (kJ per gram), aspartame is 180 times sweeter than
the others. Less aspartame is added in the soft drink, therefore less energy is consumed (the drink
has a lower energy content).