Question

at the bottom of the page, choose the separate water option.

1. in the equation, is o₂ considered a reactant or a product?
2. in the equation, is h₂o considered a reactant or a product?
3. balance the equation using the simulator. write the final coefficients below.

__ h₂o → h₂ + __ o₂

1. in the spaces below, draw the particles representing the balanced equation

box → box
at the bottom of the page, choose the combust methane option.

1. in the equation, is co₂ considered a reactant or a product?
2. balance the equation using the simulator. write the final coefficients below.

__ ch₄ + o₂ → co₂ + __ h₂o

1. in the spaces below, draw the particles representing the balanced equation

box → box

Explanation:

Step1: Identify $O_2$ role (water split)

Reactants are left of $
ightarrow$, products right. $O_2$ is on right.

Step2: Identify $H_2O$ role (water split)

$H_2O$ is left of $
ightarrow$, so it is a reactant.

Step3: Balance water splitting equation

Balance H first: 2 $H_2O$ gives 4 H, so 2 $H_2$. Then balance O: 2 $H_2O$ has 2 O, so 1 $O_2$.
Expression: $2\text{H}_2\text{O}
ightarrow 2\text{H}_2 + 1\text{O}_2$

Step4: Identify $CO_2$ role (methane combustion)

$CO_2$ is on right of $
ightarrow$, so it is a product.

Step5: Balance methane combustion equation

Balance C first: 1 $CH_4$ gives 1 $CO_2$. Balance H: 1 $CH_4$ has 4 H, so 2 $H_2O$. Balance O: 2 $H_2O$ + 1 $CO_2$ has 4 O, so 2 $O_2$.
Expression: $1\text{CH}_4 + 2\text{O}_2
ightarrow 1\text{CO}_2 + 2\text{H}_2\text{O}$

Answer:

1. Product
2. Reactant
3. 2, 2, 1 (for $\text{H}_2\text{O}$, $\text{H}_2$, $\text{O}_2$ respectively)
4. (Left box: 2 molecules of $\text{H}_2\text{O}$ (each with 1 O and 2 H atoms); Right box: 2 molecules of $\text{H}_2$ (each with 2 H atoms) and 1 molecule of $\text{O}_2$ (with 2 O atoms))
5. Product
6. 1, 2, 1, 2 (for $\text{CH}_4$, $\text{O}_2$, $\text{CO}_2$, $\text{H}_2\text{O}$ respectively)
7. (Left box: 1 molecule of $\text{CH}_4$ (1 C, 4 H atoms) and 2 molecules of $\text{O}_2$ (each with 2 O atoms); Right box: 1 molecule of $\text{CO}_2$ (1 C, 2 O atoms) and 2 molecules of $\text{H}_2\text{O}$ (each with 1 O, 2 H atoms))