Question

chemical equation: caco₃ → cao + co₂
number of atoms for each element
total number of atoms
does this equation follow law of conservation of mass?
chemical equation: cl₂ + 2kbr → 2kcl + br
number of atoms for each element
total number of atoms
does this equation follow law of conservation of mass?
chemical equation: 6co₂ + 6h₂o → c₆h₁₂o₆ + 6o₂
number of atoms for each element
total number of atoms
does this equation follow law of conservation of mass?
chemical equation: 3h₂o + 2fe → fe₂o₃ + 3h₂
number of atoms for each element
total number of atoms
does this equation follow law of conservation of mass?
chemical equation: ch₄ + 2o₂ → 2h₂o + co₂
number of atoms for each element
total number of atoms
does this equation follow law of conservation of mass?
chemical equation: 4nh₃ + 3o₂ → 4no + 6h₂o
number of atoms for each element
total number of atoms
does this equation follow law of conservation of mass?

Explanation:

Step1: Analyze $CaCO_3

ightarrow CaO + CO_2$

• Number of atoms for each element:
• Ca: 1 on left - hand side (LHS) and 1 on right - hand side (RHS).
• C: 1 on LHS and 1 on RHS.
• O: 3 on LHS (1 in $CaCO_3$) and 1 + 2=3 on RHS (1 in $CaO$ and 2 in $CO_2$).
• Total number of atoms: LHS: 1 + 1+3 = 5, RHS: 1+1 + 1+2=5.
• Law of Conservation of Mass: Since the number of atoms of each element is the same on both sides, it follows the law of conservation of mass.

Step2: Analyze $Cl_2+2KBr

ightarrow 2KCl + Br_2$

• Number of atoms for each element:
• Cl: 2 on LHS and 2 on RHS.
• K: 2 on LHS and 2 on RHS.
• Br: 2 on LHS and 2 on RHS.
• Total number of atoms: LHS: 2+2 + 2=6, RHS: 2+2+2 = 6.
• Law of Conservation of Mass: Since the number of atoms of each element is the same on both sides, it follows the law of conservation of mass.

Step3: Analyze $6CO_2+6H_2O

ightarrow C_6H_{12}O_6 + 6O_2$

• Number of atoms for each element:
• C: 6 on LHS and 6 on RHS.
• H: 12 on LHS and 12 on RHS.
• O: 12 + 6=18 on LHS and 6+12 = 18 on RHS.
• Total number of atoms: LHS: 6+12 + 18=36, RHS: 6+12+18 = 36.
• Law of Conservation of Mass: Since the number of atoms of each element is the same on both sides, it follows the law of conservation of mass.

Step4: Analyze $3H_2O+2Fe

ightarrow Fe_2O_3+3H_2$

• Number of atoms for each element:
• H: 6 on LHS and 6 on RHS.
• O: 3 on LHS and 3 on RHS.
• Fe: 2 on LHS and 2 on RHS.
• Total number of atoms: LHS: 6+3+2 = 11, RHS: 6+3+2 = 11.
• Law of Conservation of Mass: Since the number of atoms of each element is the same on both sides, it follows the law of conservation of mass.

Step5: Analyze $CH_4+2O_2

ightarrow 2H_2O+CO_2$

• Number of atoms for each element:
• C: 1 on LHS and 1 on RHS.
• H: 4 on LHS and 4 on RHS.
• O: 4 on LHS and 2 + 2=4 on RHS.
• Total number of atoms: LHS: 1+4+4 = 9, RHS: 4+2+1+2 = 9.
• Law of Conservation of Mass: Since the number of atoms of each element is the same on both sides, it follows the law of conservation of mass.

Step6: Analyze $4NH_3+3O_2

ightarrow 4NO+6H_2O$

• Number of atoms for each element:
• N: 4 on LHS and 4 on RHS.
• H: 12 on LHS and 12 on RHS.
• O: 6 on LHS and 4+6 = 10 on RHS.
• Total number of atoms: LHS: 4+12+6 = 22, RHS: 4+4+12+6 = 26.
• Law of Conservation of Mass: Since the number of atoms of each element is not the same on both sides, it does not follow the law of conservation of mass.

Answer:

• For $CaCO_3

ightarrow CaO + CO_2$:

• Number of atoms for each element: Ca: 1 - 1, C: 1 - 1, O: 3 - 3. Total number of atoms: 5 - 5. Follows law of conservation of mass.
• For $Cl_2+2KBr

ightarrow 2KCl + Br_2$:

• Number of atoms for each element: Cl: 2 - 2, K: 2 - 2, Br: 2 - 2. Total number of atoms: 6 - 6. Follows law of conservation of mass.
• For $6CO_2+6H_2O

ightarrow C_6H_{12}O_6 + 6O_2$:

• Number of atoms for each element: C: 6 - 6, H: 12 - 12, O: 18 - 18. Total number of atoms: 36 - 36. Follows law of conservation of mass.
• For $3H_2O+2Fe

ightarrow Fe_2O_3+3H_2$:

• Number of atoms for each element: H: 6 - 6, O: 3 - 3, Fe: 2 - 2. Total number of atoms: 11 - 11. Follows law of conservation of mass.
• For $CH_4+2O_2

ightarrow 2H_2O+CO_2$:

• Number of atoms for each element: C: 1 - 1, H: 4 - 4, O: 4 - 4. Total number of atoms: 9 - 9. Follows law of conservation of mass.
• For $4NH_3+3O_2

ightarrow 4NO+6H_2O$:

• Number of atoms for each element: N: 4 - 4, H: 12 - 12, O: 6 - 10. Total number of atoms: 22 - 26. Does not follow law of conservation of mass.