What is produced during the replacement reaction of Ba open paren NO sub 3 close paren sub 2 and Na sub 2 SO sub 4 ?

This is a double-replacement reaction: the ions exchange partners. Ba²⁺ combines with SO₄²⁻ to form BaSO₄, while Na⁺ combines with NO₃⁻ to form NaNO₃. Balancing the equation gives Ba(NO₃)₂ + Na₂SO₄ → 2 NaNO₃ + BaSO₄, so the products are those in choice D.

AI-written and checked against the verified answer.