Three thermochemical equations are given below:
(i) C(graphite) + O2(g) \(\rightarrow\) CO2(g); \(\Delta_{r}\)H° = x kJ mol–1
(ii) Cgraphite + 1/2 O2(g) \(\rightarrow\) CO(g); \(\Delta_{r}\)H° = y kJ mol–1
(iii) CO(g) + 1/2 O2(g) \(\rightarrow\) CO2(g); \(\Delta_{r}\)H° = z kJ mol–1
 
Based on the above equations, find out which one of the relationships given below is correct :
1. z = x + y 2. x = y + z
3. y = 2z – x 4. x = y – z
Subtopic:  Hess's Law |
 79%
Level 2: 60%+
NEET - 2013
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Which of the following statements about the advantage of roasting sulphide ore before reduction is not true?
 
1. Carbon and hydrogen act as suitable reducing agents for metal sulphides
2. The \(\Delta_f G^0\) of the sulphide is greater than those for \(C S_2\) and \(\mathrm{H}_2 \mathrm{~S}\)
3. The \(\Delta_f G^0\) is negative for roasting of sulphur ore to oxide.
4. Roasting of the sulphide to the oxide is thermodynamically feasible
Subtopic:  Gibbs Energy Change | Hess's Law |
Level 4: Below 35%
AIPMT - 2007
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