Question

for the next four reactions you will need to determine what the products will be and balance the equation.
i. zn + hcl \
ightarrow zncl + h_2
h. ch_4 + o_2 \
ightarrow co_2 + h_2o

Explanation:

Part g: $\boldsymbol{KClO_3

ightarrow KCl + O_2}$

Step1: Count atoms before balancing

Reactants: $1$ K, $1$ Cl, $3$ O
Products: $1$ K, $1$ Cl, $2$ O

Step2: Balance oxygen atoms

Add coefficient 2 to $\text{KClO}_3$, 2 to $\text{KCl}$, 3 to $\text{O}_2$:

$$2\text{KClO}_3 ightarrow 2\text{KCl} + 3\text{O}_2$$

Step3: Verify balanced atoms

Reactants: $2$ K, $2$ Cl, $6$ O
Products: $2$ K, $2$ Cl, $6$ O

---

Part h: $\boldsymbol{CH_4 + O_2

ightarrow CO_2 + H_2O}$

Step1: Count atoms before balancing

Reactants: $1$ C, $4$ H, $2$ O
Products: $1$ C, $2$ H, $3$ O

Step2: Balance hydrogen atoms

Add coefficient 2 to $\text{H}_2\text{O}$:

$$\text{CH}_4 + \text{O}_2 ightarrow \text{CO}_2 + 2\text{H}_2\text{O}$$

Step3: Balance oxygen atoms

Add coefficient 2 to $\text{O}_2$:

$$\text{CH}_4 + 2\text{O}_2 ightarrow \text{CO}_2 + 2\text{H}_2\text{O}$$

Step4: Verify balanced atoms

Reactants: $1$ C, $4$ H, $4$ O
Products: $1$ C, $4$ H, $4$ O

---

Part i: $\boldsymbol{Zn + HCl

ightarrow ZnCl_2 + H_2}$

Step1: Count atoms before balancing

Reactants: $1$ Zn, $1$ H, $1$ Cl
Products: $1$ Zn, $2$ H, $2$ Cl

Step2: Balance Cl and H atoms

Add coefficient 2 to $\text{HCl}$:

$$\text{Zn} + 2\text{HCl} ightarrow \text{ZnCl}_2 + \text{H}_2$$

Step3: Verify balanced atoms

Reactants: $1$ Zn, $2$ H, $2$ Cl
Products: $1$ Zn, $2$ H, $2$ Cl

Answer:

Part g:

Reactants	Before Balancing	After Balancing	Products	Before Balancing	After Balancing
			$\text{O}_2$	1	3

Balanced equation: $2\text{KClO}_3
ightarrow 2\text{KCl} + 3\text{O}_2$

Part h:

Reactants	Before Balancing	After Balancing	Products	Before Balancing	After Balancing
$\text{O}_2$	1	2	$\text{H}_2\text{O}$	1	2

Balanced equation: $\text{CH}_4 + 2\text{O}_2
ightarrow \text{CO}_2 + 2\text{H}_2\text{O}$

Part i:

Reactants	Before Balancing	After Balancing	Products	Before Balancing	After Balancing
$\text{HCl}$	1	2	$\text{H}_2$	1	1

Balanced equation: $\text{Zn} + 2\text{HCl}
ightarrow \text{ZnCl}_2 + \text{H}_2$