Question 151783
Note:
{{{CR[1]}}} = 1st chem. rxn
{{{CR[2]}}} = 2nd chem. rxn
{{{CR[3]}}} = 3rd chem. rxn.
{{{O[2]}}} = Oxygen produced by each rxn.
1st condition: {{{CR[1]}}} produces twice that of {{{CR[2]}}}
--------> {{{CR[1]=2O[2]}}}
--------> {{{CR[2]= O[2]}}}
2nd condition: {{{CR[3]}}} produces twice that of {{{CR[1]}}}
--------> {{{CR[3]=2(2O[2])}}}
NOW, equating the 3 values of the chemical rxn that has combined total of 560cc
{{{CR[1]+CR[2]+CR[3]=560cc}}} --------------------> working eqn
{{{2O[2]+O[2]+2(2O[2])=560cc}}}
{{{3O[2]+4O[2]=560cc}}}
{{{cross(7)O[2]/cross(7)=cross(560)80cc/cross(7)}}}
{{{O[2]=80cc}}} ----------------> amount of Oxygen produced by {{{CR[2]}}}
FOR {{{CR[1]}}}= {{{2O[2]=2*80=160cc}}}
FOR {{{CR[3]}}}= {{{2(2O[2])=2(2*80)=2(160)=320cc}}}
In doubt? Go back working eqn,
{{{160+80+320=560}}}
{{{560=560}}},  note: cc= cubic centimeter= {{{cm^3}}}
Thank you,
Jojo