# What is the net ionic equation for barium nitrate and hydrochloric acid?

Do you mean $\text{barium nitrate}$ and $\text{sulfuric acid}$?
For $B a {\left(N {O}_{3}\right)}_{2} \left(a q\right)$ and $H C l \left(a q\right)$ there would be no net macroscopic change. On the other hand, for $B a {\left(N {O}_{3}\right)}_{2} \left(a q\right)$ and ${H}_{2} S {O}_{4} \left(a q\right)$, a precipitate would form owing to the insolubility of $B a S {O}_{4}$:
$B {a}^{2 +} + S {O}_{4}^{2 -} \rightarrow B a S {O}_{4} \left(s\right) \downarrow$