Akia is balancing the equation [tex]Na + H_2O \rightarrow NaOH + H_2[/tex]. He tries to find the coefficients that will balance the equation.

How could he find the correct coefficients?

A. By counting each individual atom and making sure the number of each kind of atom is the same in the reactants and the products.

B. By counting the total atoms and making sure the number of atoms in the reactants is the same as the number of atoms in the products.

C. By counting the total mass of each compound and making sure the reactants have more mass than the products.

D. By counting the mass of each atom and making sure the reactants are more massive than the products.



Answer :

To balance a chemical equation, follow these steps:

1. List the Atoms: Write down all the different types of atoms involved in the reactants and products.

2. Count the Atoms: Count and list the number of atoms of each element present in the reactants and the products.

3. Balance One Element at a Time: Adjust the coefficients (the numbers in front of the molecules) to balance one type of atom at a time. This ensures that the number of atoms of each element is the same on both sides of the equation.

4. Check Your Work: Verify that all atoms balance out and that the same number of each type of atom appears on both sides of the equation.

Let's apply this to the given equation:

[tex]\[ Na + H_2O \rightarrow NaOH + H_2 \][/tex]

1. List the Atoms:
- Reactants: Na, H, O
- Products: Na, H, O

2. Count the Atoms:
- Reactants: Na (1), H (2 from \( H_2O \)), O (1 from \( H_2O \))
- Products: Na (1 from \( NaOH \)), H (2: 1 in \( NaOH \) + 2 in \( H_2 \)), O (1 from \( NaOH \))

3. Balance One Element at a Time:
- Start by balancing the sodium (Na) atoms. There is 1 Na atom on both sides.
- Next, balance the hydrogen (H) atoms. There are 2 H atoms on the reactant side and 3 H atoms on the product side (counting both \( NaOH \) and \( H_2 \)). To balance them, we see that each water molecule adds 2 hydrogen atoms. Adding a coefficient of 2 in front of \( H_2 O \) gives us:

[tex]\[ 2H_2O \rightarrow 2NaOH + H_2 \][/tex]

- Verify again the hydrogens: 1 Na on both sides, and 2 H from \( H_2 O \) and 2 from \( H_2 \) on the products side.

So, Akia must count each individual atom and make sure the number of each kind of atom is the same in the reactants and the products. Therefore, the correct methodology to find the coefficients to balance the equation is:

By counting each individual atom and making sure the number of each kind of atom is the same in the reactants and the products.

This process ensures the law of conservation of mass, where the mass of the reactants is equal to the mass of the products.