Final answer:
The precipitate formed in the reaction between barium nitrate and sodium chromate is barium chromate (BaCrO2).
Step-by-step explanation:
The chemical reaction between barium nitrate (Ba(NO₃)₂) and sodium chromate (Na₂CrO₄) will result in a double-replacement reaction where two new compounds are formed as products. When writing out and balancing the equation, we can predict that the possible products are barium chromate (BaCrO₄) and sodium nitrate (NaNO₃). Based on solubility rules, barium chromate is known to be insoluble in water and thus will form a precipitate. Therefore, the correct answer to which precipitate is formed in the reaction between barium nitrate and sodium chromate is (a) BaCrO2.