[KitCh]

Here is the problem:




Here is the correct reaction set arrangement:




Comments and questions:

* I understand why Reaction A was switched.
* I understand why Reaction B was multiplied by 2.
* What happened to 6O₂ from reaction A? How did it get canceled?
* Why was reaction C reversed? Wasn't 3O₂ part of the reactant? If so, why was it reversed to now have 3O₂ in the solution?


Thanks.

[orgoclear]

Ignore the solution they have provided and think on your own

In the final reaction you need 2B2O3 on the right so, you need to flip A so and multiply by 2. This gives 2B2O3 on the right.

After flipping A you get 2B2H6 on the left which is not there in the final reaction. So, you need to multiply B by 2 so that the B2H6 can cancel out.

In flipping A we get 3H2O(g) on the right. So, flip D and multiply by 3 to cancel out the H2O(g). Now in flipping D we get 3H2O(l) on the right so to cancel it flip C and multiply by 3.

Now if you add everything you should get the required reaction.

Now you should be able to understand what has been done in the solutions