Kinetics and Electrochemistry Answer Sheet
Chapter 16
1) State (gas, liquid, solution, solid and solid surface area), temperature,
concentration/pressure, the presence (or absence) of a catalyst.
12) The magnesium might be added as a fine powder or as large pieces to a
gunpowder mixture. The size of the pieces would determine how long the
magnesium will shine (burn) for — larger pieces will shine for longer. If the pieces
were too large, they might still be burning when they hit the ground. If they were
too small they would stop shining too soon.
93) increasing temperature (without increasing gas pressure)—> energy factor
heavier molecule —> energy factor
cutting into smaller pieces —> collision frequency (note that if we are very careful
about exactly how we cut the surface, we can also improve the probability factor.
This is an important part of researching new heterogeneous catalysts. You are
not expected to know this though).
adding a catalyst —> energy factor, probability factor
diluting a solution —> collision frequency
increasing gas pressure —> collision frequency
Chapter 21
9) a) Ionic solids do not conduct electricity because the ions are not free to move
towards an electrode. This means that ionic solids can not be electrolysed.
10) a) Because the magnesium instantly reacts with water to produce
magnesium hydroxide and hydrogen.
b) Because though the sodium ions are reduced to sodium metal, they then react
with water to produce sodium hydroxide and hydrogen. Since the sodium
remains as Na+ at the beginning and end of the reaction, it does not appear in
the ionic equation: 2Cl– + 2H2O —> Cl2 + H2 + 2OH– (though it does appear in
the full equation: 2NaCl + 2H2O —> Cl2 + H2 + 2NaOH).