Question

what is the formula equation for the reaction between sulfuric acid and dissolved sodium hydroxide if all products and reactants are in the aqueous or liquid phase?\
\\(\ce{hcl(aq) + naoh(aq) \
ightarrow nacl(s) + h_{2}o(l)}\\)\
\\(\ce{h_{2}so_{4}(aq) + ca(oh)_{2}(aq) \
ightarrow caso_{4}(aq) + 2h_{2}o(l)}\\)\
\\(\ce{h_{2}so_{4}(aq) + 2naoh(aq) \
ightarrow na_{2}so_{4}(aq) + 2h_{2}o(l)}\\)\
\\(\ce{2h_{3}po_{4}(aq) + 3ca(oh)_{2}(aq) \
ightarrow ca_{3}(po_{4})(s) + 6h_{2}o(l)}\\)

Explanation:

1. Analyze the reactants: The reaction is between sulfuric acid ($\ce{H2SO4}$) and sodium hydroxide ($\ce{NaOH}$).
2. Check each option:

• First option: Reactants are $\ce{HCl}$ and $\ce{NaOH}$, not sulfuric acid. Eliminate.
• Second option: Reactants are $\ce{H2SO4}$ and $\ce{Ca(OH)2}$ (calcium hydroxide), not sodium hydroxide. Eliminate.
• Third option: Reactants are $\ce{H2SO4}$ (sulfuric acid) and $\ce{NaOH}$ (sodium hydroxide). The products are $\ce{Na2SO4}$ (sodium sulfate, aqueous) and $\ce{H2O}$ (liquid), which matches the requirements (all products and reactants in aqueous or liquid phase).
• Fourth option: Reactants are phosphoric acid and calcium hydroxide, not sulfuric acid and sodium hydroxide. Eliminate.

Answer:

C. $\ce{H2SO4(aq) + 2NaOH(aq) → Na2SO4(aq) + 2H2O(l)}$ (Note: Using option identifier as per the original, assuming the third option is C here. If the original options were labeled A, B, C, D, then the correct one is the third option, say C, with the formula as above.)