Question

aqueous sodium sulfide reacts with hydrochloric acid.
what is the balanced chemical equation for this reaction?
na₂s (aq) + hcl (aq) → h₂s (aq)+ nacl (aq)
nas(aq) + hcl(aq) → hs(g)+ nacl(aq)
na₂s(aq)+ 2hcl(aq) → h₂s(g)+ 2nacl(aq)
na₂s (aq) + hcl (aq) → h₂s (g)+ nacl (aq)

Explanation:

Step1: Identify reactants and products

Reactants: $\text{Na}_2\text{S}(aq)$, $\text{HCl}(aq)$; Products: $\text{H}_2\text{S}$, $\text{NaCl}(aq)$

Step2: Balance sodium atoms

There are 2 Na on left, add 2 to $\text{NaCl}$:
$\text{Na}_2\text{S}(aq) + \text{HCl}(aq)
ightarrow \text{H}_2\text{S}(g) + 2\text{NaCl}(aq)$

Step3: Balance chlorine atoms

There are 2 Cl on right, add 2 to $\text{HCl}$:
$\text{Na}_2\text{S}(aq) + 2\text{HCl}(aq)
ightarrow \text{H}_2\text{S}(g) + 2\text{NaCl}(aq)$

Step4: Verify all atoms

Na: 2=2; S:1=1; H:2=2; Cl:2=2. All balanced.

Answer:

Na₂S(aq)+2HCl(aq) → H₂S(g)+2NaCl(aq)