textbook problem 5.35

[karen 2c]

Hi! I'm having trouble understanding the balanced equation for the reaction based on the graph. I get that it's supposed to be written in this format: A (g) <-- --> B(g) + C(g) based on the description but I'm not understanding why it says 2A (g) <-- --> B(g) + 2C(g)... Where did the 2 come from??

[605775499]

Consider the poorly formatted (sorry) ICE table:
........A B C
I ....27.5 0 0
C ....-10 +5 +10
E ....17.5 5 10

we can construct this because we know the initial and final amounts. notice that if X=5, both A and C have a "2x" in the change section, meaning they have coefficients in the chemical formula