Chemical energy turns into heat and light energy.
There’s energy stored(potential) in the log, so when it burns, that energy is released as light and heat
What are the half equations from earlier? It says use those and I can’t do it without them?
Answer:
Solution III < Solution II < Solution I < Solution IV
Explanation:
I)
Due to the rate of neutralization is 1 mol of NaOH with 1 mol of HCl and that we have equal volumes of both solution with the same concentration, they neutralize each other leaving a neutral pH (pH=7). Althought, because your titrating agent is a base the equivalence point will be a bit alkaline.
II) The same as the point I) but now the titrating agent is the acid, the equivalence point will be neutral trending a bit to acid.
III) Given that we have one strong acid neutralizing a weak base solution, in the equivalence point the the pH will be acid because the HCl (strong) dissociates compleately so we will have the 0.01 mol (100 ml of 0.1 M) of HCl with 0.01 mol>CH3NH2 (because is a weak base). How much less than 0.01 mol we have? <u>It depends of the strengh of the base and the pH will also depend on that</u>.
IV) This case is similar to the last one but with a strong base and a weak acid. So with a similar deduction the pH in the equivalence point will be alkaline (pH>7). How much? It depends on the strengh of the acid.
<u>In order of increasing pH: </u>
Solution III < Solution II < Solution I < Solution IV
In order to know the number of moles from the given mass, the conversion factor to be used is the average atomic mass of Calcium which is equal to 40.08 g/mol. But first, let's convert mass from grams to kilograms knowing that there are 1,000 g in every 1 kg.
Mass = 351 kg * 1,000g/1 kg = 351,000 grams
Number of moles = 351,000 g * 1 mol/40.08 g = 8,757.5 moles Calcium