Answer:
There is only one possible value for the quantity "c"
Explanation:
There is only one possible value for the quantity "c". This is because the a,b,c and d represent number of moles in he balanced equation. And since the number of moles of a particular substance (atom or compound) in a balanced equation must be distinct, it (the substance) can only have one value. For example, consider the equation below
2C₂H₂ + 5O₂ ⇒ 4CO₂ + 2H₂O
It can be seen from the above equation that the individual number of moles are distinct and have just one possible value. And if Câ‚‚Hâ‚‚ is A, Oâ‚‚ is B, COâ‚‚ is C and Hâ‚‚O is D, then 4 is "c".
Thus, "c" is the number of moles for the substance "C" with just one possible value.