The reactions shown here can be combined to make the overall reaction C(s) + H2O(g) ⇌ CO(g) + H2(g) by reversing some and/or dividing all the coefficients by a number. a. C(s) + O2(g) → CO2(g) K=1.363×10^69 b. 2 H2(g) + O2(g) → 2 H2O(g) K=1.389×10^80 c. 2CO(g) + O2 (g) → 2 CO2(g) K=1.477×10^90

Explanation:

Overall reaction :

C(s) + H2O(g) ⇌ CO(g) + H2(g)

First Reaction :

C(s) + O2(g) → CO2(g)

Second Reaction :

2 H2(g) + O2(g) → 2 H2O(g)

Third Reaction :

2CO(g) + O2 (g) → 2 CO2(g)

To obtain the overall reaction

- Multiply the first reaction by 2. The equation we have is;

2C(s) + 2O2(g) → 2CO2(g)

- Add the reaction with the reversed second reaction. The equation we have is given as;

2C(s) + 2O2(g) + 2 H2O(g)   → 2 H2(g) + O2(g) +  2CO2(g)

Simplifying we have;

2C(s)  + 2 H2O(g)  + O2(g) → 2 H2(g) +  2CO2(g)

- Add the new equation with the reversed third equation. We have;

2C(s)  + 2H2O(g) + 2CO2(g) + O2(g)  → 2 H2(g) +  2CO2(g)  + 2CO(g) + O2 (g)

Simplifying we have;

2C(s)  + 2 H2O(g)  → 2 H2(g)  + 2CO(g)

Divide the reaction by 2. We have;

C(s) + H2O(g) ⇌ CO(g) + H2(g)

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.

c, liquids evaporate, creating a gas