When 6.4 g of `NaHCO_(3)` is added to a solution of `CH_(3)COOH` weighing 20. It is observed that 4.4 g of `CO_(2)` is released into atmosphere and a residue is left behind Calculate the mass of residue by applying law of conservation of mass.

Answer

To calculate the mass of the residue left behind when 6.4 g of NaHCO₃ is added to a solution of CH₃COOH weighing 20 g, and 4.4 g of CO₂ is released, we can apply the law of conservation of mass. Here’s the step-by-step solution:

### Step 1: Identify the mass of reactants
The total mass of the reactants is the sum of the mass of NaHCO₃ and the mass of CH₃COOH.

- Mass of NaHCO₃ = 6.4 g
- Mass of CH₃COOH = 20 g

Total mass of reactants = Mass of NaHCO₃ + Mass of CH₃COOH
Total mass of reactants = 6.4 g + 20 g = 26.4 g

### Step 2: Identify the mass of products
The products of the reaction include the released CO₂ and the residue left behind.

- Mass of CO₂ released = 4.4 g
- Let the mass of the residue be represented as X g.

### Step 3: Apply the law of conservation of mass
According to the law of conservation of mass, the total mass of the reactants must equal the total mass of the products.

Total mass of reactants = Total mass of products
26.4 g = Mass of CO₂ + Mass of residue
26.4 g = 4.4 g + X

### Step 4: Solve for the mass of the residue
Now, we can rearrange the equation to find the mass of the residue (X):

X = Total mass of reactants - Mass of CO₂
X = 26.4 g - 4.4 g
X = 22 g

### Conclusion
The mass of the residue left behind is 22 g.

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