Question

1. _ ca + _ $h_2o$ → _ $ca(oh)_2$ + _ $h_2$
2. _ $secl_6$ + _ $o_2$ → _ $seo_2$ + _ $cl_2$
3. _ $ch_4$ + _ $o_2$ → _ $co_2$ + _ $h_2o$
4. _ $kclo_3$ → _ $kcl$ + ___ $o_2$
5. _ $s_8$ + _ $o_2$ → ___ $so_2$
6. _ $p_4$ + _ $o_2$ → ___ $p_2o_5$

Explanation:

Step1: Balance Ca atoms

Ca: 1 on left, 1 on right. Coefficient for Ca = 1, $\text{Ca(OH)}_2$ = 1.

Step2: Balance H atoms

H: 2 on left, 4 on right. Coefficient for $\text{H}_2\text{O}$ = 2.

Step3: Balance O atoms

O: 2 on left, 2 on right. Balanced.

Step4: Verify all atoms

Ca:1=1, H:4=4, O:2=2. Equation 9 balanced.

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Step1: Balance Se atoms

Se:1 on left,1 on right. Coefficient for $\text{SeCl}_6$=1, $\text{SeO}_2$=1.

Step2: Balance Cl atoms

Cl:6 on left,2 on right. Coefficient for $\text{Cl}_2$=3.

Step3: Balance O atoms

O:2 on left,2 on right. Coefficient for $\text{O}_2$=1.

Step4: Verify all atoms

Se:1=1, Cl:6=6, O:2=2. Equation10 balanced.

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Step1: Balance C atoms

C:1 on left,1 on right. Coefficient for $\text{CH}_4$=1, $\text{CO}_2$=1.

Step2: Balance H atoms

H:4 on left,2 on right. Coefficient for $\text{H}_2\text{O}$=2.

Step3: Balance O atoms

O:2 on left,4 on right. Coefficient for $\text{O}_2$=2.

Step4: Verify all atoms

C:1=1, H:4=4, O:4=4. Equation11 balanced.

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Step1: Balance K, Cl atoms

K,Cl:1 on left,1 on right. Coefficient for $\text{KClO}_3$=2, $\text{KCl}$=2.

Step2: Balance O atoms

O:6 on left,2 on right. Coefficient for $\text{O}_2$=3.

Step3: Verify all atoms

K:2=2, Cl:2=2, O:6=6. Equation12 balanced.

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Step1: Balance S atoms

S:8 on left,1 on right. Coefficient for $\text{S}_8$=1, $\text{SO}_2$=8.

Step2: Balance O atoms

O:2 on left,16 on right. Coefficient for $\text{O}_2$=8.

Step3: Verify all atoms

S:8=8, O:16=16. Equation13 balanced.

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Step1: Balance P atoms

P:4 on left,2 on right. Coefficient for $\text{P}_4$=1, $\text{P}_2\text{O}_5$=2.

Step2: Balance O atoms

O:2 on left,10 on right. Coefficient for $\text{O}_2$=5.

Step3: Verify all atoms

P:4=4, O:10=10. Equation14 balanced.

Answer:

1. $\boldsymbol{1\ \text{Ca} + 2\ \text{H}_2\text{O}

ightarrow 1\ \text{Ca(OH)}_2 + 1\ \text{H}_2}$

1. $\boldsymbol{1\ \text{SeCl}_6 + 1\ \text{O}_2

ightarrow 1\ \text{SeO}_2 + 3\ \text{Cl}_2}$

1. $\boldsymbol{1\ \text{CH}_4 + 2\ \text{O}_2

ightarrow 1\ \text{CO}_2 + 2\ \text{H}_2\text{O}}$

1. $\boldsymbol{2\ \text{KClO}_3

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

1. $\boldsymbol{1\ \text{S}_8 + 8\ \text{O}_2

ightarrow 8\ \text{SO}_2}$

1. $\boldsymbol{1\ \text{P}_4 + 5\ \text{O}_2

ightarrow 2\ \text{P}_2\text{O}_5}$