To balance the given equation, we start with the unbalanced equation:
\[ \text{Na}_2\text{S} + \text{HCl} \rightarrow \text{NaCl} + \text{H}_2\text{S} \]
Now, let's balance it step by step.
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Count the number of each type of atom on both sides:
- Left side: \( \text{Na} = 2, \text{S} = 1, \text{H} = 1, \text{Cl} = 1 \)
- Right side: \( \text{Na} = 1, \text{Cl} = 1, \text{H} = 2, \text{S} = 1 \)
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Balance the sodium (Na) atoms:
- There are 2 Na on the left side, so we need 2 NaCl on the right side.
- Adjust the equation: \[ \text{Na}_2\text{S} + \text{HCl} \rightarrow 2 \text{NaCl} + \text{H}_2\text{S} \]
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Balance the hydrochloric acid (HCl) molecules:
- Now, we have:
- Left side: \( \text{Na} = 2, \text{Cl} = 1, \text{H} = 1, \text{S} = 1 \)
- Right side: \( \text{Na} = 2, \text{Cl} = 2, \text{H} = 2, \text{S} = 1 \)
- We need 2 HCl on the left side: \[ \text{Na}_2\text{S} + 2 \text{HCl} \rightarrow 2 \text{NaCl} + \text{H}_2\text{S} \]
- Now, we have:
Final balanced equation: \[ \text{Na}_2\text{S} + 2 \text{HCl} \rightarrow 2 \text{NaCl} + \text{H}_2\text{S} \]