# On the basis of thermochemical equations (a), (b) and (c), find out which of the algebraic relationships given in options (i) to (iv) is correct.(a) $C (graphite)+O_{2}(g)\rightarrow CO_{2}(g);\Delta _{r}H=x\; kJ\; mol^{-1}$(b) $C (graphite)+\frac{1}{2}O_{2}(g)\rightarrow CO(g);\Delta _{r}H=y\; kJ\; mol^{-1}$(c) $CO _{(g)} + \frac{1}{2}O_{2(g)}\rightarrow CO_{2(g)} ; \Delta _{r}H= z\; kJ\; mol^{-1}$(i) z = x + y (ii) x = y – z (iii) x = y + z (iv) y = 2z – x

The answer is option (iii) x = y + z

x =y + z is the correct option as Algebraic sum of y and z will give x.

Explanation: When y is subtracted from x, we get z. Explained below:

$C (graphite)+O_{2}(g)\rightarrow CO_{2}(g);\Delta _{r}H=x\; kJ\; mol^{-1}$________(i)

$C (graphite)+\frac{1}{2}O_{2}(g)\rightarrow CO(g);\Delta _{r}H=y\; kJ\; mol^{-1}$________(ii)

$CO _{(g)} + \frac{1}{2}O_{2(g)}\rightarrow CO_{2(g)} ; \Delta _{r}H= z\; kJ\; mol^{-1}$________(iii)

So, z= x-y, or, easily put, x=y+z. Hence, option c.

## Most Viewed Questions

### Preparation Products

##### Knockout NEET 2024

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 40000/-
##### Knockout NEET 2025

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 45000/-
##### NEET Foundation + Knockout NEET 2024

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 54999/- ₹ 42499/-
##### NEET Foundation + Knockout NEET 2024 (Easy Installment)

Personalized AI Tutor and Adaptive Time Table, Self Study Material, Unlimited Mock Tests and Personalized Analysis Reports, 24x7 Doubt Chat Support,.

₹ 3999/-