text: is na2co3 acidic or basic when dissolved in water?   na2co3 + 2h2o --> 2naoh + h2co3  naoh is soluble in water, so 2 moles of oh- will form. h2co3 is a weak acid that does not dissociate fully in water, so there will be fewer than 2 moles of h+ present.  as there is more oh-, the solution will be basic.